Whales and dolphins lead ‘human-like lives’ thanks to big brains, says study

The cultural brain hypothesis of human development could also explain cetaceans forming friendships and even gossiping

Life is not so different beneath the ocean waves. Bottlenose dolphins use simple tools, orcas call each other by name, and sperm whales talk in local dialects. Many cetaceans live in tight-knit groups and spend a good deal of time at play.

That much scientists know. But in a new study, researchers compiled a list of the rich behaviours spotted in 90 different species of dolphins, whales and porpoises, and found that the bigger the species brain, the more complex indeed, the more human-like their lives are likely to be.

This suggests that the cultural brain hypothesis the theory that suggests our intelligence developed as a way of coping with large and complex social groups may apply to whales and dolphins, as well as humans.

Writing in the journal, Nature Ecology and Evolution, the researchers claim that complex social and cultural characteristics, such as hunting together, developing regional dialects and learning from observation, are linked to the expansion of the animals brains a process known as encephalisation.

The researchers gathered records of dolphins playing with humpback whales, helping fishermen with their catches, and even producing signature whistles for dolphins that are absent suggesting the animals may even gossip.

Another common behaviour was adult animals raising unrelated young. There is the saying that it takes a village to raise a child [and that] seems to be true for both whales and humans, said Michael Muthukrishna, an economic psychologist and co-author on the study at the London School of Economics.

Dolphins
Dolphins off the coast of South Africa. Photograph: Rainer Schimpf/Barcroft Media

Like humans, the cetaceans, a group made up of dolphins, whales and porpoises, are thought to do most of their learning socially rather than individually, which could explain why some species learn more complex behaviours than others. Those predominantly found alone or in small groups had the smallest brains, the researchers led by Susanne Shultz at the University of Manchester wrote.

Luke Rendell, a biologist at the University of St Andrews who was not involved in the study, but has done work on sperm whales and their distinctive dialects, warned against anthropomorphising and making animals appear to be like humans.

There is a risk of sounding like there is a single train line, with humans at the final station and other animals on their way of getting there. The truth is that every animal responds to their own evolutionary pressures, he said.

There is definitely a danger in comparing other animals to humans, especially with the data available. But what we can say for sure, is that this cultural-brain hypothesis we tested is present in primates and in cetaceans, Muthukrishna said.

There was still much more to learn, though, he added. Studies with underwater mammals are difficult and vastly underfunded, so there is so much we dont know about these fascinating animals, he said.

The fascination, however, should not only be interesting for people studying animals. We dont have to look at other planets to look for aliens, because we know that underwater there are these amazing species with so many parallels to us in their complex behaviours, said Muthukrishna.

Studying evolutionarily distinct animals such as cetaceans could act as a control group for studying intelligence in general, and so help the understanding of our own intellect.

It is interesting to think that whale and human brains are different in their structure but have brought us to the same patterns in behaviour, Rendell said. The extent of how this is close to humans can educate us about evolutionary forces in general.

However, Muthukrishna points out that intelligence is always driven by the environment an animal finds itself in. Each environment presents a different set of challenges for an animal. When you are above water, you learn how to tackle fire, for example, he said. As smart as whales are, they will never learn to light a spark.

Source: http://www.theguardian.com/us

Three-eyed extinct reptile was a bone-headed dinosaur mimic 100 million years early

Newly discovered Triopticus primus is one of many copy-cat animals

A bizarre new extinct reptile with a domed skull of solid bone has been unearthed in Texas. If this sounds familiar, it could be because you have heard of a group of dinosaurs called the pachycephalosaurs that possessed very similar characteristics. One could almost call Triopticus a mimic were it not for the fact that it dates to 228-220 million years ago, meaning that it predates the pachycephalosaurs by over 100 million years. Moreover, Triopticus is one of numerous animals from this period (the Late Triassic) that were in some way copies of other reptiles that evolved later.

Triopticus is a small animal the preserved dome of the skull is only around 5 cm long even though it is from an adult animal, but what there is of it is very unusual. There is a large pit in the skull that resembles the eye sockets of reptiles and gave rise to the animals name, as Triopticus means three eyes. This hole does not represent an extra eye, however, but may simply be a result of the surrounding bones having enlarged and expanded leaving this space behind, rather than there being a bit missing.

Aside from the difference of this divot, comparisons to the pachycephalosaurs are more than superficial. Both have greatly enlarged domes of solid bone that sat at the back of the head above the brain, both show some extra bumps and bosses, and both even show some similarities in the microstructure of the bone. Although the rest of Triopticus is missing, it is hard not to suggest that these animals may have bashed heads with one another as the pachycephalosaurs are thought to do (although this is not covered in the paper). Such similarities of form between only distantly related organisms is termed convergent evolution and there are numerous examples of this in the fossil record and alive today (think of the hydrodynamic shapes of fish, dolphins and penguins).

Convergent
Convergent evolution between Triassic animals (left) and those that came later (right) and in particular Triopticus and pachycephalosaurs (both top) Photograph: Stocker et al., 2016

However, Triopticus and a number of the reptiles that lived alongside it show some remarkable convergences with other reptiles that came later, and most notably the dinosaurs. In the Late Triassic there were various animals showing adaptations and body plans that will be familiar to those who have browsed even childrens books on dinosaurs. There were bipedal plant eating reptiles similar to the ornithomimosaurs, herbivorous forms with leaf-shaped teeth covered in armour like the later ankylosaurs, large-headed reptiles with sharp teeth that looked like predatory dinosaurs (if on four legs rather than two), and even long-snouted semi-aquatic animals that resembled extinct and even living crocodilians.

These pairs are already known to palaeontologists, but an analysis of skull and body shapes shows how similar animals were to each other in the ages before the dinosaurs and others diverged, and then later how similar these various different forms became, despite their fairly distant relatedness. Its notable that Triopticus is a particular outlier, being even more distant from the ancestral form that the pachycephalosaurs it has quite an extreme set of anatomical features.

That convergent evolution is rampant within some groups is not big news, but the sheer range of extinct reptile species that ended up taking on similar forms (and often more than once) is a reminder of the selective pressures that evolution can bring to some lineages. Even so these are typically limited to classic ecological features like specialised teeth for eating or claws for digging, so modify the skull in such a shape more than once as seen here is quite a surprise and one hopes that more will come to light in the future. It will certainly be interesting to see if the rest of Triopticus matches the thick-headed dinosaurs in any other areas.

Source: http://www.theguardian.com/us

Peculiar Ancient Marine Reptile Reveals Life Evolved Rapidly After “Great Dying Apocalypse

The end-Permian mass extinction 252 million years ago was by far the worst in the entire history of the world; an apocalypse by any other name. Over 90 percent of all life on Earth died, including a terrifying 96 percent of all marine species. It was a true evolutionary bottleneck, one that the survivors barely managed to get through.

It is colloquially and appropriately known as the Great Dying, and the infamous dinosaurian extinction event 66 million years ago simply pales in comparison. A long-held assumption among many paleontologists was that during this time of epic prolonged volcanism, rapid climate change and dramatic sea level fluctuations, the rate of the evolution of new marine species was relatively slow.

However, a new study describing a peculiar new fossil throws this theory into some disrepute. This bizarre marine reptile, named Sclerocormus parviceps, is a type of ichthyosauriform, which were beasts that generally resembled contemporary dolphins but belonged to a distinct evolutionary lineage.

Living from 250 million years to around 90 million years ago, they were particularly abundant during the early Jurassic period (201 to 174 million years ago). This new specimen was found in a Chinese geological formation just over 248 million years old, meaning that this ichthyosauriform is one of the most evolutionarily primitive ever found.

A different ichthyosaur, the Shonisaurus.Catmando/Shutterstock

We don’t have many marine reptile fossils from this period, Dr. Olivier Rieppel, a researcher andcurator at the Field Museum in Chicago and co-author of the paper, said in a statement. This specimen is important because it suggests that there’s diversity that hasn’t been uncovered yet.

As described in the journal Scientific Reports, this newly discovered species looked entirely different from what paleontologists have come to expect. Most of these aquatic creatures had long beak-like snouts, streamlined hydrodynamic bodies, sharp conical teeth, and powerful tail fins.

This new 1.6-meter-long (5.25 feet) fellow had a shorter snout, smaller skull, and a long whip-like tail with a lack of large fins.Most distinct of all, it was toothless. Researchers think that it used its snout to suck up prey, like a biological syringe.

The fact that it is so very different from its descendants shows that the evolution of these apex predators was actually far more rapid than previously thought. Within the space of just 50 to 80 million years or so, they had diversified into a plethora of forms.

Sclerocormustells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period, Rieppel added. Darwin’s model of evolution consists of small, gradual changes over a long period of time, and that’s not quite what we’re seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds.

The new fossil, Sclerocormus parviceps. Da-yong Jiang

This remarkable find does more than just add resolution to the story of the ichthyosaurs, whose extinction was recently blamed on them becoming too specialized and ultimately losing their ecological niche to others. It also shows researchers how life responds to a mass extinction event, which in this case was the mother of all extinction events, immediately after the event itself.

Although this particular species of ichthyosauriform went extinct soon after it evolved, it beautifully showcases the types of aquatic features that natural selection deemed to be appropriate at a time of huge environmental change. Ultimately, though, this fossil raises more questions than it answers, most prominently of all being this: How was this line of marine reptiles able to evolve so incredibly quickly right after life on Earth almost ended?

Photo Gallery

Source: http://www.iflscience.com

Three-eyed extinct reptile was a bone-headed dinosaur mimic 100 million years early

Newly discovered Triopticus primus is one of many copy-cat animals

A bizarre new extinct reptile with a domed skull of solid bone has been unearthed in Texas. If this sounds familiar, it could be because you have heard of a group of dinosaurs called the pachycephalosaurs that possessed very similar characteristics. One could almost call Triopticus a mimic were it not for the fact that it dates to 228-220 million years ago, meaning that it predates the pachycephalosaurs by over 100 million years. Moreover, Triopticus is one of numerous animals from this period (the Late Triassic) that were in some way copies of other reptiles that evolved later.

Triopticus is a small animal the preserved dome of the skull is only around 5 cm long even though it is from an adult animal, but what there is of it is very unusual. There is a large pit in the skull that resembles the eye sockets of reptiles and gave rise to the animals name, as Triopticus means three eyes. This hole does not represent an extra eye, however, but may simply be a result of the surrounding bones having enlarged and expanded leaving this space behind, rather than there being a bit missing.

Aside from the difference of this divot, comparisons to the pachycephalosaurs are more than superficial. Both have greatly enlarged domes of solid bone that sat at the back of the head above the brain, both show some extra bumps and bosses, and both even show some similarities in the microstructure of the bone. Although the rest of Triopticus is missing, it is hard not to suggest that these animals may have bashed heads with one another as the pachycephalosaurs are thought to do (although this is not covered in the paper). Such similarities of form between only distantly related organisms is termed convergent evolution and there are numerous examples of this in the fossil record and alive today (think of the hydrodynamic shapes of fish, dolphins and penguins).

Convergent
Convergent evolution between Triassic animals (left) and those that came later (right) and in particular Triopticus and pachycephalosaurs (both top) Photograph: Stocker et al., 2016

However, Triopticus and a number of the reptiles that lived alongside it show some remarkable convergences with other reptiles that came later, and most notably the dinosaurs. In the Late Triassic there were various animals showing adaptations and body plans that will be familiar to those who have browsed even childrens books on dinosaurs. There were bipedal plant eating reptiles similar to the ornithomimosaurs, herbivorous forms with leaf-shaped teeth covered in armour like the later ankylosaurs, large-headed reptiles with sharp teeth that looked like predatory dinosaurs (if on four legs rather than two), and even long-snouted semi-aquatic animals that resembled extinct and even living crocodilians.

These pairs are already known to palaeontologists, but an analysis of skull and body shapes shows how similar animals were to each other in the ages before the dinosaurs and others diverged, and then later how similar these various different forms became, despite their fairly distant relatedness. Its notable that Triopticus is a particular outlier, being even more distant from the ancestral form that the pachycephalosaurs it has quite an extreme set of anatomical features.

That convergent evolution is rampant within some groups is not big news, but the sheer range of extinct reptile species that ended up taking on similar forms (and often more than once) is a reminder of the selective pressures that evolution can bring to some lineages. Even so these are typically limited to classic ecological features like specialised teeth for eating or claws for digging, so modify the skull in such a shape more than once as seen here is quite a surprise and one hopes that more will come to light in the future. It will certainly be interesting to see if the rest of Triopticus matches the thick-headed dinosaurs in any other areas.

Source: http://www.theguardian.com/us

Dog DNA study reveals the incredible journey of man’s best friend

Descended from the grey wolf, domesticated dogs have been companions to humans for about 33,000 years, a genetic study has shown

Mans proverbial first best friend was probably a grey wolf that may have made contact with the first human companions about 33,000 years ago, somewhere in south-east Asia.

About 15,000 years ago, a small pack of domesticated dogs began trotting towards the Middle East and Africa. Canis lupus familiaris made it to Europe about 10,000 years ago, and when civilisation began in the Fertile Crescent, and humans began to build farmsteads and villages with walls, dogs were already there to help keep guard, herd the first flocks, and demand to be taken for a walk.

The details of the story the characters, the action and the precise locations are unknowable. But the outlines of the great adventure are written in DNA.

Scientists from China, Canada, Finland, Singapore, Sweden and the US report in the journal Cell Research that they compared the genomes, or genetic inheritances, of 58 canids. These included 12 grey wolves, 12 indigenous dogs from the north Chinese countryside, 11 from south-east Asia, four village dogs from Nigeria and 19 specimens of selective breeding from Asia, Europe and the Americas, including the Afghan hound, the Siberian husky, the Tibetan mastiff, the chihuahua and the German shepherd.

Because each genome is a text copied (with regular misspellings, or mutations) through the generations, and every genome is related to every other genome, any comparison begins to tell a story of family connections and separations long ago. The more texts that can be compared, the more certain the story they start to tell.

After evolving for several thousand years in east Asia, a subgroup of dogs radiated out of southern East Asia about 15,000 years ago to the Middle East, Africa as well as Europe. One of these out-of-Asia lineages then migrated back to northern China and made a series of admixtures with endemic east Asian lineages, before travelling to the Americas, the scientists say.

Our study, for the first time, reveals the extraordinary journey that the domestic dog has travelled on this planet during the past 33,000 years.

The grey wolf connection has been made before, along with the link with East Asia. The scientists, led by Guo-Dong Wang, a molecular biologist at the Kunming Institute of Zoology, have once more confirmed it. The indigenous Chinese dogs revealed closer links to their wolf ancestors, and retained the greatest genetic variety, another indicator that the domestic canine began somewhere in East Asia. The modern European specialist breeds showed less genetic diversity, suggesting that they descended from a subset of the first dogs, and the DNA of village dogs of Africa showed even less diversity, implying that they owed their origins to an even smaller set of migrant ancestors.

But the same genetic evidence suggests that at least some dogs from Europe and western Asia may have travelled back into China to interbreed, complicating the story. The ancestral dog and wolf may have continued to interbreed for a while, but the scientists are confident enough of their findings not only to put a date for the emergence of what became the domestic dog around 33,000 years ago but even to guess at an original or founder population of about 4,600 individuals.

Whether these joined forces with Ice Age human hunter gatherers, or whether they stayed as wild as the wolves, scavenging on human kills, and subsequently joined up with human companions as part of the civilisation package about 15,000 years ago on the journey to the west, is still uncertain.

Our study, for the first time, begins to reveal a large and complex landscape upon which a cascade of positive selective sweeps occurred during the domestication of dogs, the scientists write. The domestic dog represents one of the most beautiful genetic sculptures shaped by nature and man.

Source: http://www.theguardian.com/us

Peculiar Ancient Marine Reptile Reveals Life Evolved Rapidly After “Great Dying Apocalypse

The end-Permian mass extinction 252 million years ago was by far the worst in the entire history of the world; an apocalypse by any other name. Over 90 percent of all life on Earth died, including a terrifying 96 percent of all marine species. It was a true evolutionary bottleneck, one that the survivors barely managed to get through.

It is colloquially and appropriately known as the Great Dying, and the infamous dinosaurian extinction event 66 million years ago simply pales in comparison. A long-held assumption among many paleontologists was that during this time of epic prolonged volcanism, rapid climate change and dramatic sea level fluctuations, the rate of the evolution of new marine species was relatively slow.

However, a new study describing a peculiar new fossil throws this theory into some disrepute. This bizarre marine reptile, named Sclerocormus parviceps, is a type of ichthyosauriform, which were beasts that generally resembled contemporary dolphins but belonged to a distinct evolutionary lineage.

Living from 250 million years to around 90 million years ago, they were particularly abundant during the early Jurassic period (201 to 174 million years ago). This new specimen was found in a Chinese geological formation just over 248 million years old, meaning that this ichthyosauriform is one of the most evolutionarily primitive ever found.

A different ichthyosaur, the Shonisaurus.Catmando/Shutterstock

We don’t have many marine reptile fossils from this period, Dr. Olivier Rieppel, a researcher andcurator at the Field Museum in Chicago and co-author of the paper, said in a statement. This specimen is important because it suggests that there’s diversity that hasn’t been uncovered yet.

As described in the journal Scientific Reports, this newly discovered species looked entirely different from what paleontologists have come to expect. Most of these aquatic creatures had long beak-like snouts, streamlined hydrodynamic bodies, sharp conical teeth, and powerful tail fins.

This new 1.6-meter-long (5.25 feet) fellow had a shorter snout, smaller skull, and a long whip-like tail with a lack of large fins.Most distinct of all, it was toothless. Researchers think that it used its snout to suck up prey, like a biological syringe.

The fact that it is so very different from its descendants shows that the evolution of these apex predators was actually far more rapid than previously thought. Within the space of just 50 to 80 million years or so, they had diversified into a plethora of forms.

Sclerocormustells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period, Rieppel added. Darwin’s model of evolution consists of small, gradual changes over a long period of time, and that’s not quite what we’re seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds.

The new fossil, Sclerocormus parviceps. Da-yong Jiang

This remarkable find does more than just add resolution to the story of the ichthyosaurs, whose extinction was recently blamed on them becoming too specialized and ultimately losing their ecological niche to others. It also shows researchers how life responds to a mass extinction event, which in this case was the mother of all extinction events, immediately after the event itself.

Although this particular species of ichthyosauriform went extinct soon after it evolved, it beautifully showcases the types of aquatic features that natural selection deemed to be appropriate at a time of huge environmental change. Ultimately, though, this fossil raises more questions than it answers, most prominently of all being this: How was this line of marine reptiles able to evolve so incredibly quickly right after life on Earth almost ended?

Photo Gallery

Source: http://www.iflscience.com

Three-eyed extinct reptile was a bone-headed dinosaur mimic 100 million years early

Newly discovered Triopticus primus is one of many copy-cat animals

A bizarre new extinct reptile with a domed skull of solid bone has been unearthed in Texas. If this sounds familiar, it could be because you have heard of a group of dinosaurs called the pachycephalosaurs that possessed very similar characteristics. One could almost call Triopticus a mimic were it not for the fact that it dates to 228-220 million years ago, meaning that it predates the pachycephalosaurs by over 100 million years. Moreover, Triopticus is one of numerous animals from this period (the Late Triassic) that were in some way copies of other reptiles that evolved later.

Triopticus is a small animal the preserved dome of the skull is only around 5 cm long even though it is from an adult animal, but what there is of it is very unusual. There is a large pit in the skull that resembles the eye sockets of reptiles and gave rise to the animals name, as Triopticus means three eyes. This hole does not represent an extra eye, however, but may simply be a result of the surrounding bones having enlarged and expanded leaving this space behind, rather than there being a bit missing.

Aside from the difference of this divot, comparisons to the pachycephalosaurs are more than superficial. Both have greatly enlarged domes of solid bone that sat at the back of the head above the brain, both show some extra bumps and bosses, and both even show some similarities in the microstructure of the bone. Although the rest of Triopticus is missing, it is hard not to suggest that these animals may have bashed heads with one another as the pachycephalosaurs are thought to do (although this is not covered in the paper). Such similarities of form between only distantly related organisms is termed convergent evolution and there are numerous examples of this in the fossil record and alive today (think of the hydrodynamic shapes of fish, dolphins and penguins).

Convergent
Convergent evolution between Triassic animals (left) and those that came later (right) and in particular Triopticus and pachycephalosaurs (both top) Photograph: Stocker et al., 2016

However, Triopticus and a number of the reptiles that lived alongside it show some remarkable convergences with other reptiles that came later, and most notably the dinosaurs. In the Late Triassic there were various animals showing adaptations and body plans that will be familiar to those who have browsed even childrens books on dinosaurs. There were bipedal plant eating reptiles similar to the ornithomimosaurs, herbivorous forms with leaf-shaped teeth covered in armour like the later ankylosaurs, large-headed reptiles with sharp teeth that looked like predatory dinosaurs (if on four legs rather than two), and even long-snouted semi-aquatic animals that resembled extinct and even living crocodilians.

These pairs are already known to palaeontologists, but an analysis of skull and body shapes shows how similar animals were to each other in the ages before the dinosaurs and others diverged, and then later how similar these various different forms became, despite their fairly distant relatedness. Its notable that Triopticus is a particular outlier, being even more distant from the ancestral form that the pachycephalosaurs it has quite an extreme set of anatomical features.

That convergent evolution is rampant within some groups is not big news, but the sheer range of extinct reptile species that ended up taking on similar forms (and often more than once) is a reminder of the selective pressures that evolution can bring to some lineages. Even so these are typically limited to classic ecological features like specialised teeth for eating or claws for digging, so modify the skull in such a shape more than once as seen here is quite a surprise and one hopes that more will come to light in the future. It will certainly be interesting to see if the rest of Triopticus matches the thick-headed dinosaurs in any other areas.

Source: http://www.theguardian.com/us

Evolution row ends as scientists declare sponges to be sister of all other animals

Question of whether sponges or comb jellies were first to branch off the evolutionary tree from the common ancestor of all animals may be answered

A longstanding row in animal evolution has come to a head, with a team of scientists claiming they have ended the debate over which type of creature is the sister of all other animals.

Researchers have been torn for years over whether sponges or marine invertebrates known as comb jellies were the first type of creature to branch off the evolutionary tree from the common ancestor of all animals.

Now researchers say the debate is over: the sponges have won.

We need to try to understand the sponges much better if we want to understand the nature of animals and our own deepest ancestry, said Davide Pisani, co-author of the research and professor of phylogenomics at the University of Bristol.

The finding, say experts, is no trivial matter, as it could have drastic implications for what the last common ancestor of all animals looked like.

Sponges are simple humble, in a sense creatures that live at the bottom of the sea; they are filter-feeders, they dont do much, said Pisani. The comb jelly is a very different creature. They are extremely pretty and rather complicated, he added, pointing out that comb jellies look a bit like jellyfish and can propel themselves through water, create patterns of light and have both a simple nervous system and a gut including a mouth and anus.

A
A Mnemiopsis leidyi, a species of comb jelly known as a sea walnut. Photograph: AP

If the comb jellies are the sister of all of us, then we either are in a situation where the last common ancestor of all the animals was quite complex, [having] a nervous system, a gut and muscles and then the sponges [lost these features] or all these things we see in the comb jellies evolved multiple times in animals, he said, adding that the scenario also posed other puzzles such as what the ancestral creature would have preyed on.

If the sponges are the sister group of everything else then we can assume a much simpler scenario, said Pisani. Then the assumption is we evolved from a filter-feeder organism.

With different models of evolutionary relationships applied to the same genetic data throwing up either a triumph for the sponge side of the debate or the comb jellies, the researchers of latest study turned to statistics to resolve the issue.

With this type of approach you can evaluate the extent to which alternative models are capable of describing a dataset, so you can say this model is good for this specific dataset and this model is not good, said Pisani.

The results, published in the journal Current Biology, were clear, he said. Models that provide a much better description of the data invariably find the sponges at the root of the tree, for all of the datasets that have been published up to now.

That, he adds, ties in well with the fact that the closest living relatives of all animals are filter-feeding aquatic organisms called choanoflagellates.

But the findings he said, should offer us all food for thought. I think part of why people love this debate so much is the comb jellies are beautiful and the sponges are somewhat ugly. The sponge is the underdog in a sense, he said. So it is quite nice to know that we have really humble beginnings, rather than this glamorous start.

While Pisani believes proponents of the comb jellies might continue the debate, he says the wrangle is drawing to a close. From my perspective, yes, this is the last word, he said.

Antonis Rokas, professor of biological sciences and biomedical informatics at Vanderbilt University, and who has previously published studies supporting the idea that comb jellies are the oldest sister group to all other animals, welcomed the research. [It] is a great step in the right direction toward resolving the debate, he said, adding that the analyses comparing the accuracy of models are insightful.

But, he said, the new approach brings with it its own difficulties, leading him to believe the jury is still out. With this study, the authors have significantly tipped the balance toward the sponges-sister hypothesis, he said. But I will eagerly await to see what are the effects of adding additional genomes from both sponge and ctenophore lineages, as well as models that do not reduce the information provided from the data, before considering the debate solved.

Source: http://www.theguardian.com/us

Whales and dolphins lead ‘human-like lives’ thanks to big brains, says study

The cultural brain hypothesis of human development could also explain cetaceans forming friendships and even gossiping

Life is not so different beneath the ocean waves. Bottlenose dolphins use simple tools, orcas call each other by name, and sperm whales talk in local dialects. Many cetaceans live in tight-knit groups and spend a good deal of time at play.

That much scientists know. But in a new study, researchers compiled a list of the rich behaviours spotted in 90 different species of dolphins, whales and porpoises, and found that the bigger the species brain, the more complex indeed, the more human-like their lives are likely to be.

This suggests that the cultural brain hypothesis the theory that suggests our intelligence developed as a way of coping with large and complex social groups may apply to whales and dolphins, as well as humans.

Writing in the journal, Nature Ecology and Evolution, the researchers claim that complex social and cultural characteristics, such as hunting together, developing regional dialects and learning from observation, are linked to the expansion of the animals brains a process known as encephalisation.

The researchers gathered records of dolphins playing with humpback whales, helping fishermen with their catches, and even producing signature whistles for dolphins that are absent suggesting the animals may even gossip.

Another common behaviour was adult animals raising unrelated young. There is the saying that it takes a village to raise a child [and that] seems to be true for both whales and humans, said Michael Muthukrishna, an economic psychologist and co-author on the study at the London School of Economics.

Dolphins
Dolphins off the coast of South Africa. Photograph: Rainer Schimpf/Barcroft Media

Like humans, the cetaceans, a group made up of dolphins, whales and porpoises, are thought to do most of their learning socially rather than individually, which could explain why some species learn more complex behaviours than others. Those predominantly found alone or in small groups had the smallest brains, the researchers led by Susanne Shultz at the University of Manchester wrote.

Luke Rendell, a biologist at the University of St Andrews who was not involved in the study, but has done work on sperm whales and their distinctive dialects, warned against anthropomorphising and making animals appear to be like humans.

There is a risk of sounding like there is a single train line, with humans at the final station and other animals on their way of getting there. The truth is that every animal responds to their own evolutionary pressures, he said.

There is definitely a danger in comparing other animals to humans, especially with the data available. But what we can say for sure, is that this cultural-brain hypothesis we tested is present in primates and in cetaceans, Muthukrishna said.

There was still much more to learn, though, he added. Studies with underwater mammals are difficult and vastly underfunded, so there is so much we dont know about these fascinating animals, he said.

The fascination, however, should not only be interesting for people studying animals. We dont have to look at other planets to look for aliens, because we know that underwater there are these amazing species with so many parallels to us in their complex behaviours, said Muthukrishna.

Studying evolutionarily distinct animals such as cetaceans could act as a control group for studying intelligence in general, and so help the understanding of our own intellect.

It is interesting to think that whale and human brains are different in their structure but have brought us to the same patterns in behaviour, Rendell said. The extent of how this is close to humans can educate us about evolutionary forces in general.

However, Muthukrishna points out that intelligence is always driven by the environment an animal finds itself in. Each environment presents a different set of challenges for an animal. When you are above water, you learn how to tackle fire, for example, he said. As smart as whales are, they will never learn to light a spark.

Source: http://www.theguardian.com/us

Peculiar Ancient Marine Reptile Reveals Life Evolved Rapidly After “Great Dying Apocalypse

The end-Permian mass extinction 252 million years ago was by far the worst in the entire history of the world; an apocalypse by any other name. Over 90 percent of all life on Earth died, including a terrifying 96 percent of all marine species. It was a true evolutionary bottleneck, one that the survivors barely managed to get through.

It is colloquially and appropriately known as the Great Dying, and the infamous dinosaurian extinction event 66 million years ago simply pales in comparison. A long-held assumption among many paleontologists was that during this time of epic prolonged volcanism, rapid climate change and dramatic sea level fluctuations, the rate of the evolution of new marine species was relatively slow.

However, a new study describing a peculiar new fossil throws this theory into some disrepute. This bizarre marine reptile, named Sclerocormus parviceps, is a type of ichthyosauriform, which were beasts that generally resembled contemporary dolphins but belonged to a distinct evolutionary lineage.

Living from 250 million years to around 90 million years ago, they were particularly abundant during the early Jurassic period (201 to 174 million years ago). This new specimen was found in a Chinese geological formation just over 248 million years old, meaning that this ichthyosauriform is one of the most evolutionarily primitive ever found.

A different ichthyosaur, the Shonisaurus.Catmando/Shutterstock

We don’t have many marine reptile fossils from this period, Dr. Olivier Rieppel, a researcher andcurator at the Field Museum in Chicago and co-author of the paper, said in a statement. This specimen is important because it suggests that there’s diversity that hasn’t been uncovered yet.

As described in the journal Scientific Reports, this newly discovered species looked entirely different from what paleontologists have come to expect. Most of these aquatic creatures had long beak-like snouts, streamlined hydrodynamic bodies, sharp conical teeth, and powerful tail fins.

This new 1.6-meter-long (5.25 feet) fellow had a shorter snout, smaller skull, and a long whip-like tail with a lack of large fins.Most distinct of all, it was toothless. Researchers think that it used its snout to suck up prey, like a biological syringe.

The fact that it is so very different from its descendants shows that the evolution of these apex predators was actually far more rapid than previously thought. Within the space of just 50 to 80 million years or so, they had diversified into a plethora of forms.

Sclerocormustells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period, Rieppel added. Darwin’s model of evolution consists of small, gradual changes over a long period of time, and that’s not quite what we’re seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds.

The new fossil, Sclerocormus parviceps. Da-yong Jiang

This remarkable find does more than just add resolution to the story of the ichthyosaurs, whose extinction was recently blamed on them becoming too specialized and ultimately losing their ecological niche to others. It also shows researchers how life responds to a mass extinction event, which in this case was the mother of all extinction events, immediately after the event itself.

Although this particular species of ichthyosauriform went extinct soon after it evolved, it beautifully showcases the types of aquatic features that natural selection deemed to be appropriate at a time of huge environmental change. Ultimately, though, this fossil raises more questions than it answers, most prominently of all being this: How was this line of marine reptiles able to evolve so incredibly quickly right after life on Earth almost ended?

Photo Gallery

Source: http://www.iflscience.com

Three-eyed extinct reptile was a bone-headed dinosaur mimic 100 million years early

Newly discovered Triopticus primus is one of many copy-cat animals

A bizarre new extinct reptile with a domed skull of solid bone has been unearthed in Texas. If this sounds familiar, it could be because you have heard of a group of dinosaurs called the pachycephalosaurs that possessed very similar characteristics. One could almost call Triopticus a mimic were it not for the fact that it dates to 228-220 million years ago, meaning that it predates the pachycephalosaurs by over 100 million years. Moreover, Triopticus is one of numerous animals from this period (the Late Triassic) that were in some way copies of other reptiles that evolved later.

Triopticus is a small animal the preserved dome of the skull is only around 5 cm long even though it is from an adult animal, but what there is of it is very unusual. There is a large pit in the skull that resembles the eye sockets of reptiles and gave rise to the animals name, as Triopticus means three eyes. This hole does not represent an extra eye, however, but may simply be a result of the surrounding bones having enlarged and expanded leaving this space behind, rather than there being a bit missing.

Aside from the difference of this divot, comparisons to the pachycephalosaurs are more than superficial. Both have greatly enlarged domes of solid bone that sat at the back of the head above the brain, both show some extra bumps and bosses, and both even show some similarities in the microstructure of the bone. Although the rest of Triopticus is missing, it is hard not to suggest that these animals may have bashed heads with one another as the pachycephalosaurs are thought to do (although this is not covered in the paper). Such similarities of form between only distantly related organisms is termed convergent evolution and there are numerous examples of this in the fossil record and alive today (think of the hydrodynamic shapes of fish, dolphins and penguins).

Convergent
Convergent evolution between Triassic animals (left) and those that came later (right) and in particular Triopticus and pachycephalosaurs (both top) Photograph: Stocker et al., 2016

However, Triopticus and a number of the reptiles that lived alongside it show some remarkable convergences with other reptiles that came later, and most notably the dinosaurs. In the Late Triassic there were various animals showing adaptations and body plans that will be familiar to those who have browsed even childrens books on dinosaurs. There were bipedal plant eating reptiles similar to the ornithomimosaurs, herbivorous forms with leaf-shaped teeth covered in armour like the later ankylosaurs, large-headed reptiles with sharp teeth that looked like predatory dinosaurs (if on four legs rather than two), and even long-snouted semi-aquatic animals that resembled extinct and even living crocodilians.

These pairs are already known to palaeontologists, but an analysis of skull and body shapes shows how similar animals were to each other in the ages before the dinosaurs and others diverged, and then later how similar these various different forms became, despite their fairly distant relatedness. Its notable that Triopticus is a particular outlier, being even more distant from the ancestral form that the pachycephalosaurs it has quite an extreme set of anatomical features.

That convergent evolution is rampant within some groups is not big news, but the sheer range of extinct reptile species that ended up taking on similar forms (and often more than once) is a reminder of the selective pressures that evolution can bring to some lineages. Even so these are typically limited to classic ecological features like specialised teeth for eating or claws for digging, so modify the skull in such a shape more than once as seen here is quite a surprise and one hopes that more will come to light in the future. It will certainly be interesting to see if the rest of Triopticus matches the thick-headed dinosaurs in any other areas.

Source: http://www.theguardian.com/us

Peculiar Ancient Marine Reptile Reveals Life Evolved Rapidly After “Great Dying Apocalypse

The end-Permian mass extinction 252 million years ago was by far the worst in the entire history of the world; an apocalypse by any other name. Over 90 percent of all life on Earth died, including a terrifying 96 percent of all marine species. It was a true evolutionary bottleneck, one that the survivors barely managed to get through.

It is colloquially and appropriately known as the Great Dying, and the infamous dinosaurian extinction event 66 million years ago simply pales in comparison. A long-held assumption among many paleontologists was that during this time of epic prolonged volcanism, rapid climate change and dramatic sea level fluctuations, the rate of the evolution of new marine species was relatively slow.

However, a new study describing a peculiar new fossil throws this theory into some disrepute. This bizarre marine reptile, named Sclerocormus parviceps, is a type of ichthyosauriform, which were beasts that generally resembled contemporary dolphins but belonged to a distinct evolutionary lineage.

Living from 250 million years to around 90 million years ago, they were particularly abundant during the early Jurassic period (201 to 174 million years ago). This new specimen was found in a Chinese geological formation just over 248 million years old, meaning that this ichthyosauriform is one of the most evolutionarily primitive ever found.

A different ichthyosaur, the Shonisaurus.Catmando/Shutterstock

We don’t have many marine reptile fossils from this period, Dr. Olivier Rieppel, a researcher andcurator at the Field Museum in Chicago and co-author of the paper, said in a statement. This specimen is important because it suggests that there’s diversity that hasn’t been uncovered yet.

As described in the journal Scientific Reports, this newly discovered species looked entirely different from what paleontologists have come to expect. Most of these aquatic creatures had long beak-like snouts, streamlined hydrodynamic bodies, sharp conical teeth, and powerful tail fins.

This new 1.6-meter-long (5.25 feet) fellow had a shorter snout, smaller skull, and a long whip-like tail with a lack of large fins.Most distinct of all, it was toothless. Researchers think that it used its snout to suck up prey, like a biological syringe.

The fact that it is so very different from its descendants shows that the evolution of these apex predators was actually far more rapid than previously thought. Within the space of just 50 to 80 million years or so, they had diversified into a plethora of forms.

Sclerocormustells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period, Rieppel added. Darwin’s model of evolution consists of small, gradual changes over a long period of time, and that’s not quite what we’re seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds.

The new fossil, Sclerocormus parviceps. Da-yong Jiang

This remarkable find does more than just add resolution to the story of the ichthyosaurs, whose extinction was recently blamed on them becoming too specialized and ultimately losing their ecological niche to others. It also shows researchers how life responds to a mass extinction event, which in this case was the mother of all extinction events, immediately after the event itself.

Although this particular species of ichthyosauriform went extinct soon after it evolved, it beautifully showcases the types of aquatic features that natural selection deemed to be appropriate at a time of huge environmental change. Ultimately, though, this fossil raises more questions than it answers, most prominently of all being this: How was this line of marine reptiles able to evolve so incredibly quickly right after life on Earth almost ended?

Photo Gallery

Read more: http://www.iflscience.com/plants-and-animals/peculiar-ancient-marine-reptile-reveals-life-evolved-rapidly-after-great-dying

New species of ‘weird bird’-like dinosaur discovered in China

Named Tongtianlong limosus – which means muddy dragon on the road to heaven – the dinosaur appears to have died after getting stuck in the mud

A farmer and construction workers in China have discovered the remains of a new species of bird-like dinosaur that appears to have died after getting stuck in the mud. The find, experts say, adds weight to the idea that such animals were thriving shortly before the mass extinction 66 million years ago.

Around the size of a sheep, with a beak, wings and a crest on its head, the flightless creature is thought to be a species of oviraptorosaur – a group of bird-like, feathered, toothless and short-skulled non-avian dinosaurs that were roaming the land in the period shortly before an asteroid slammed into Earth off the coast of Mexico, triggering the annihilation of swaths of life.

If you saw it alive you would just think it was a weird bird, said Stephen Brusatte, a palaeontologist at the University of Edinburgh who, with colleagues in China, co-authored the research published in the journal Scientific Reports.

The
The remains of Tongtianlong limosus, discovered by a farmer and construction workers in China. Photograph: Junchang Lu

But the newly discovered dinosaur appears to have suffered an untimely demise. It looked like it got trapped in mud, and thats how it died, said Brusatte. The neck is arched, the head is raised up, like its sticking its head above something, and both of the arms are outstretched and to the sides of the body, and so its like its trying to free itself.

Named Tongtianlong limosus – muddy dragon on the road to heaven – the dinosaurs fossilised remains were discovered on the building site of a high school near Ganxian, in the Jiangxi Province of southern China. The fossils were unearthed by construction workers who were using TNT to blast away rocks – an activity which, while unexpectedly bringing the dinosaurs remains to light, also appears to have blown away parts of the fossil, including sections of its arms and tail and its right hind leg.

A
A conservator works alongside the new find. Photograph: Junchang Lu

Thought to have lived between 72 million and 66 million years ago, the newly discovered dinosaur sheds light on the ecosystem just before the fateful asteroid struck. Not only were there still a lot of dinosaurs, but they were still actively diversifying – there were still many new species that were coming about, said Brusatte.

Brusatte adds that the new discovery joins a number of recent oviraptorosaur finds from southern China, suggesting that such bird-like omnivores were on the rise before falling foul of the mass extinction. What it is looking like is that these things were probably pretty common parts of the dinosaur ecosystem, he said. This really was probably the last wave of dinosaur diversification before the asteroid came.

Paul Upchurch, professor of palaeobiology at University College London who was not involved in the research, said that while the posture of the dinosaur was unusual, there was little to be gleaned from the pose. No-one knows what it means, he said. Its an odd quirk, but scientifically it doesnt take us anywhere.

But, he added, the discovery of a new species of oviraptorosaur adds weight to the argument that rather than being in decline before the mass extinction, dinosaurs might have been flourishing. It doesnt win the argument one way or the other, but it is another point in favour, perhaps, of suggesting that there were certainly some places in the world where they were doing absolutely fine, he said.

Read more: https://www.theguardian.com/science/2016/nov/10/new-species-of-weird-bird-like-dinosaur-discovered-in-china-tongtianlong-limosus

Oldest fossil of bird’s voicebox gives new hint at soundscape of the Cretaceous

66m-year-old syrinx of Vegavis iaai suggests that creature could honk and quack and confirms some modern bird groups lived alongside the dinosaurs

The oldest evidence of a birds voice box has been found among the fossilised remains of a duck-like creature that lived more than 66 million years ago.

The discovery suggests that the animal was able to make a variety of sounds similar to those of current day ducks, including quacks.

The human voice box, or larynx, sits near the top of the windpipe. However, the vocal organ of birds – known as a syrinx – lies deep within the chest near the heart, where the windpipe branches to the lungs. Composed of cartilage rings and soft tissue, it allows birds to make a wide variety of calls, from songs to honks.

But little is known about the origin of the organ.

Now scientists says they have found the remains of a syrinx within the fossilised, partial skeleton of a bird, known as Vegavis iaai, that lived in the age of the dinosaurs.

What was really striking is that it is basically all of the informative parts of the voice box; it is the business part of the syrinx, said Julia Clarke, first author of the new research from the University of Texas at Austin.

The findings, she added, offer important clues as to the evolution of the vocal organ of birds, and potentially of the communication strategies and social interactions the syrinx underpins.

The
The fossil syrinx is from the late Cretaceous of Antarctica (middle image). Within dinosaurs there was a transition from a vocal organ present in the larynx (found in crocodiles) to one that has uniquely developed deep in the chest in birds. Photograph: J. Clarke/UT Austin

Stephen Brusatte, a palaeontologist at Edinburgh University, described the new find as a stunning discovery.

The bones themselves are a really important fossil they are one of the oldest good skeletons of a modern-style bird, and confirm that some of the bird groups that around today, like ducks and geese, were also living with the dinosaurs, he said.

But the discovery also offers a new perspective on soundscape that would have existed more than 66 million years ago.

It tells us that these early birds living alongside the dinosaurs may have sounded like some of the birds around today, Brusatte said. If [we] were standing back in the late Cretaceous, during that calm before the asteroid hit and wiped out the dinosaurs, the air may have been filled with the songs, chirps, and honks of birds!

Discovered within the rocks of Vega Island in the Antarctic in 1992, Vegavis iaai was classified by a team including Clarke as an early relative of ducks and geese in 2005, making it the only species of modern bird known to have lived at the time of the dinosaurs.

Writing in the journal Nature, Clarke and colleagues from the US, China and Argentina describe how they discovered the syrinx among its fossilised remains using high resolution x-ray techniques. From the resulting three-dimensional digital model, the team were able to analyse the organ and determine that it had a diameter of around 1cm.

The
The fossil syrinx is from an extinct species related to ducks from the late Cretaceous of Antarctica. Within dinosaurs there was a transition from a vocal organ present in the larynx (seen in crocodiles) to one uniquely developed where the windpipe branches towards the lungs in birds. Illustration: J. Clarke/Nicole Fuller/Sayo Art for UT Austin

The team then compared the syrinx to vocal organs from 12 bird species alive today, as well as the larynx of an American alligator. The team also analysed for the first time a syrinx previously found in the fossilised remains of a species of long-legged waterfowl that lived around 50 million years ago.

The results enabled the researchers to explore the evolution of the syrinx and make predictions about what early forms of the organ would have looked like.

That a syrinx has not been found in any other dinosaur, avian or non-avian, from before the mass extinction at the end of the Cretaceous suggests that the development of the the organ was a relatively late step in the evolution of birds, the authors say.

The team of us have spent the last two years trying to find even earlier syrinxes and we havent [found one], said Clarke. We suggest [the syrinx] might be a late- arriving phenomenon, after the origin of flight and respiratory innovation like continuous breathing.

Non-avian dinosaurs, such as the Tyrannosaurus rex, she added, would probably have had a larynx and most likely made loud booming sounds.

Read more: https://www.theguardian.com/science/2016/oct/12/oldest-fossil-of-birds-voicebox-gives-new-hint-at-soundscape-of-the-cretaceous-syrinx

Three-eyed extinct reptile was a bone-headed dinosaur mimic 100 million years early

Newly discovered Triopticus primus is one of many copy-cat animals

A bizarre new extinct reptile with a domed skull of solid bone has been unearthed in Texas. If this sounds familiar, it could be because you have heard of a group of dinosaurs called the pachycephalosaurs that possessed very similar characteristics. One could almost call Triopticus a mimic were it not for the fact that it dates to 228-220 million years ago, meaning that it predates the pachycephalosaurs by over 100 million years. Moreover, Triopticus is one of numerous animals from this period (the Late Triassic) that were in some way copies of other reptiles that evolved later.

Triopticus is a small animal the preserved dome of the skull is only around 5 cm long even though it is from an adult animal, but what there is of it is very unusual. There is a large pit in the skull that resembles the eye sockets of reptiles and gave rise to the animals name, as Triopticus means three eyes. This hole does not represent an extra eye, however, but may simply be a result of the surrounding bones having enlarged and expanded leaving this space behind, rather than there being a bit missing.

Aside from the difference of this divot, comparisons to the pachycephalosaurs are more than superficial. Both have greatly enlarged domes of solid bone that sat at the back of the head above the brain, both show some extra bumps and bosses, and both even show some similarities in the microstructure of the bone. Although the rest of Triopticus is missing, it is hard not to suggest that these animals may have bashed heads with one another as the pachycephalosaurs are thought to do (although this is not covered in the paper). Such similarities of form between only distantly related organisms is termed convergent evolution and there are numerous examples of this in the fossil record and alive today (think of the hydrodynamic shapes of fish, dolphins and penguins).

Convergent
Convergent evolution between Triassic animals (left) and those that came later (right) and in particular Triopticus and pachycephalosaurs (both top) Photograph: Stocker et al., 2016

However, Triopticus and a number of the reptiles that lived alongside it show some remarkable convergences with other reptiles that came later, and most notably the dinosaurs. In the Late Triassic there were various animals showing adaptations and body plans that will be familiar to those who have browsed even childrens books on dinosaurs. There were bipedal plant eating reptiles similar to the ornithomimosaurs, herbivorous forms with leaf-shaped teeth covered in armour like the later ankylosaurs, large-headed reptiles with sharp teeth that looked like predatory dinosaurs (if on four legs rather than two), and even long-snouted semi-aquatic animals that resembled extinct and even living crocodilians.

These pairs are already known to palaeontologists, but an analysis of skull and body shapes shows how similar animals were to each other in the ages before the dinosaurs and others diverged, and then later how similar these various different forms became, despite their fairly distant relatedness. Its notable that Triopticus is a particular outlier, being even more distant from the ancestral form that the pachycephalosaurs it has quite an extreme set of anatomical features.

That convergent evolution is rampant within some groups is not big news, but the sheer range of extinct reptile species that ended up taking on similar forms (and often more than once) is a reminder of the selective pressures that evolution can bring to some lineages. Even so these are typically limited to classic ecological features like specialised teeth for eating or claws for digging, so modify the skull in such a shape more than once as seen here is quite a surprise and one hopes that more will come to light in the future. It will certainly be interesting to see if the rest of Triopticus matches the thick-headed dinosaurs in any other areas.

Read more: https://www.theguardian.com/science/2016/sep/28/triopticus-three-eyed-extinct-reptile-was-a-bone-headed-dinosaur-mimic-100-million-years-early

The fabulous fossils of Messel – a colourful world of birds and beetles

Fossil oil shales open a window into the early diversity of mammals and the radiation of birds with spectacular fossils

The fossil record is crap. The chances of an organism becoming fossilised are small, and the chance of us finding said fossil are even smaller. More often than not, the fossils that we do find consist of mere fragments of an organism, rather than complete and intact animals or plants. These tattered specimens provide us with a tiny, cracked peephole through which we attempt to view the past. It is like reconstructing the world based on your three-year old nieces drawings.

However, every now and then, we stumble upon a treasure trove of fossils that somehow withstood the test of time, and show us not just a glimpse, but a whole scene from a lost world. A Rembrandt between the stick figures, if you will.

The fossil fauna from Messel near the city of Darmstadt in Germany is one of those spectacular fossil assemblages. The Messel quarry was mined for more than a century for its oil shales, and it was during these mining activities that workers discovered that the sediments contained beautifully preserved fossils of animals and plants. Messels sediments were laid down during the Eocene Epoch, about 47 million years ago, in what was then a crater lake surrounded by a subtropical rainforest. The release of toxic volcanic gasses is believed to have led to the death of many animals.

The
There is not much to see today, but the Messel quarry was once home to a lush tropical forest buzzing with life. Photograph: Werner Bayer

Soft-tissue preservation is rare in the fossil record, as it is mostly the hard bits, such as bones and teeth, which survive. However, low levels of oxygen in the lakes waters and little disturbance of the sediments at the bottom of the lake resulted in the exceptional preservation of animals; animals are often preserved whole with soft tissue preservation, and even small details such as hairs, feathers and stomach contents can be observed. This extremely good preservation has earned Messel the name Konservat-Lagerstatte, a German term to indicate a paleontological site with exceptional preservation conditions, and the site is now a UNESCO heritage site.

The diversity in Messels fauna is staggering. There are thousands of delicate insect fossils, some of them even with their colouration preserved. Fish fossils are extremely abundant, and fossil reptiles include crocodiles and alligators, snakes and turtles. At the time of deposition of Messels fossil fauna, the Age of Mammals was in full swing and the first members of modern groups appear during this time.

The Messel fauna contains numerous species of mammals including possums, pangolins, bats and rodents, but one of the better known species is the Messel horse Eurohippus messelensis. The size of a cat, and with nail-like hooflets instead of nails, it looks nothing like a modern horse, but it is an early member of a group that later gave rise to horses. The preservation of many Eurohippus messelensis specimens is so exceptional that researchers were able to observe that several mares were pregnant at the time of their death, and even details of the foetus milk teeth can be seen!

A more notorious member of the Messel mammals is the early primate Darwinius masillae. Known from only one specimen, nicknamed Ida, this species was thought to represent a missing link between early primates and anthropoids, the group of primates that would ultimately give rise to humans. However, this hypothesis was later criticised.

An
Specimen of the Messel horse Eurohippus messelensis with a fetus preserved (in circle). Photograph: Werner Bayer

Although Messel is famed for its fossil mammals, birds are the most abundant and species-rich group of land vertebrates. So far some 70 species have been identified, some of them still awaiting formal description, and many are known from multiple specimens. As a bird palaeontologist who usually only has fragmentary bones to work with, seeing all these beautifully preserved bird skeletons induces a great deal on envy. Not only are many of the Messel bird specimens fairly complete (knowing which leg bone goes with which wing bone is a privilege in the field of bird palaeontology), many of them also contain traces of feathers, and in some cases, internal organ structures and glands.

Although the Messel birds range from tiny hummingbird-like birds to the two-metre-tall, flightless predator Gastornis – a group of large flightless birds with heavy, hooked beaks – most species tend to be small to medium-sized. This is thought to be due to the fact that the smaller arboreal and insectivore species which foraged on insects above the lake surface had a bigger chance of ending up in the lake sediments than the larger species foraging on the forest floor.

Some of the bird species found in Messel are closely related to living species, such as the early trogon Masillatrogon pumilio and the swift Scaniacypselus. However, the Messel avifauna includes many extinct groups without close living relatives or with unknown affinities, such as the long-legged and flightless Palaeotis weigelti, the aptly named Perplexicervix microcephalon, and the small, presumably nectarivorous, Pumiliornis. A specimen of the latter species was found with pollen grains preserved in its stomach, representing the first recorded occurrence of flower-visiting by birds. By far the most abundant species though is the Messel rail Messelornis, an extinct long-legged relative of modern rails, with at least 340 individual specimens.

Part
Just some of the diverse collection of fossil bird fossils from Messel. (A) The Messel rail Messelornis (Messelornithidae); (B) the large, flightless Strigogyps (Ameghinornithidae); (C) the halcyornithid Pseudasturides; (D) the nectarivorous Pumiliornis (inset shows detail of pollen grains, preserved as stomach contents); (E) the nyctibiiform Paraprefica; (F) the swift-like apodiform Scaniacypselus; (G) the podargiform Masillapodargus; (H) the coliiforms Masillacolius and (I) Chascacocolius; and (J) the upupiform Messelirrisor. Photograph: Gerald Mayr

Notably absent from the Messel avifauna are songbirds, the most abundant bird group in modern forest habitats. Songbirds originated in the Southern Hemisphere, and their major radiation post-dates the Eocene period. The high number of species and the ecological diversity observed in the Messel avifauna resembles that of a modern tropical forest. The stability of tropical ecosystems has long been thought to have been the driving force behind the high species richness. Simply put, old groups would have had more time for diversification than younger ones. However, for some groups of modern tropical forest birds with early representatives already present in Messel, species richness remains low today. In addition, the most species-rich groups today, such as pigeons, parrots and songbirds, are absent from Messel and other early Eocene assemblages. This suggests that, in addition to age, other factors are at play that affect the diversity of tropical avifaunas.

In addition to the dazzling array of bird species, Messel gives us a valuable perspective on the origin of the high species diversity of tropical ecosystems. As with many a masterpiece, the longer you look, the more you see.

Read more: https://www.theguardian.com/science/2016/may/18/the-fabulous-fossils-of-messel-a-colourful-world-of-birds-and-beetles

Just Like Humans, Killer Whales Culture Is Driving Their Evolution

Just because they cant sing opera or ride a unicycle doesnt mean that animals dont have culture, and theres no better example of this than the killer whale. As one of the most brutal predators on the planet, orcas may not fit the profile of a cultured creature. However,these beasts of the sea do display a vast range of highly refined behaviors that appear to be driving their genetic development, according to new research.

The word culture comes from the Latin colere, which literally means to cultivate. In other words, it refers to anything that is acquired or learnt, rather than instinctive or natural. Among human populations, culture not only affects the way we live, but also writes itself into our genes, affecting who we are.

For instance, having spent many generations hunting the blubbery marine mammals of the Arctic, the Inuit of Greenland have developed certain genetic adaptations that help them digest and utilize this lipid-rich diet, thereby allowing them to thrive in their cold climate.

Like humans, killer whales have colonized a range of different habitats across the globe, occupying every ocean basin on the planet, with an empire that extends from pole to pole. As such, different populations of orcas have had to learn different hunting techniques in order to gain the upper hand over their local prey. This, in turn, has a major effect on their diet, leading scientists to speculate that the ability to learn population-specific hunting modalities could be driving the animals genetic development.

Publishing their findings in the journal Nature Communications, an international team of scientists explain how they analyzed the genomes of 50 orcas from five different populations, inhabiting a range of locations in the North Pacific and Antarctic Oceans.

Among the whales included in the study, some came from populations known to feed mainly on penguins, some ate a diet consisting mostly of mammals and others feasted on fish. After examining their genetic make-up, the researchers found that the orcas fit into five neat ecotypes, or genetically distinct geographic varieties of whale, thereby indicating just how synchronized their genes are with their culture.

They suggest this has occurred as populations have developed highly specialized, often ingenious hunting techniques such as the creation of artificial waves in order to knock seals off ice floes, as made famous by the BBCs Frozen Planet documentary series. By teaching these strategies to their young, the whales have developed a deep-rooted culture, reinforcing their diet and leading to certain selective pressures upon their genes.

For example, fish-eating ecotypes were found to carry certain genes that enabled them to more effectively digest their scaly prey, while those that hunt blubbery mammals were more genetically attuned to this fatty diet.

All in all, the study authors suggest that culture-genome evolution may not be exclusive to humans after all, and urge other researchers to place more focus on the role of animals culture in driving their genetics.

Read more: http://www.iflscience.com/plants-and-animals/just-humans-killer-whales-culture-driving-their-evolution

Peculiar Ancient Marine Reptile Reveals Life Evolved Rapidly After “Great Dying Apocalypse

The end-Permian mass extinction 252 million years ago was by far the worst in the entire history of the world; an apocalypse by any other name. Over 90 percent of all life on Earth died, including a terrifying 96 percent of all marine species. It was a true evolutionary bottleneck, one that the survivors barely managed to get through.

It is colloquially and appropriately known as the Great Dying, and the infamous dinosaurian extinction event 66 million years ago simply pales in comparison. A long-held assumption among many paleontologists was that during this time of epic prolonged volcanism, rapid climate change and dramatic sea level fluctuations, the rate of the evolution of new marine species was relatively slow.

However, a new study describing a peculiar new fossil throws this theory into some disrepute. This bizarre marine reptile, named Sclerocormus parviceps, is a type of ichthyosauriform, which were beasts that generally resembled contemporary dolphins but belonged to a distinct evolutionary lineage.

Living from 250 million years to around 90 million years ago, they were particularly abundant during the early Jurassic period (201 to 174 million years ago). This new specimen was found in a Chinese geological formation just over 248 million years old, meaning that this ichthyosauriform is one of the most evolutionarily primitive ever found.

A different ichthyosaur, the Shonisaurus.Catmando/Shutterstock

We don’t have many marine reptile fossils from this period, Dr. Olivier Rieppel, a researcher andcurator at the Field Museum in Chicago and co-author of the paper, said in a statement. This specimen is important because it suggests that there’s diversity that hasn’t been uncovered yet.

As described in the journal Scientific Reports, this newly discovered species looked entirely different from what paleontologists have come to expect. Most of these aquatic creatures had long beak-like snouts, streamlined hydrodynamic bodies, sharp conical teeth, and powerful tail fins.

This new 1.6-meter-long (5.25 feet) fellow had a shorter snout, smaller skull, and a long whip-like tail with a lack of large fins.Most distinct of all, it was toothless. Researchers think that it used its snout to suck up prey, like a biological syringe.

The fact that it is so very different from its descendants shows that the evolution of these apex predators was actually far more rapid than previously thought. Within the space of just 50 to 80 million years or so, they had diversified into a plethora of forms.

Sclerocormustells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period, Rieppel added. Darwin’s model of evolution consists of small, gradual changes over a long period of time, and that’s not quite what we’re seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds.

The new fossil, Sclerocormus parviceps. Da-yong Jiang

This remarkable find does more than just add resolution to the story of the ichthyosaurs, whose extinction was recently blamed on them becoming too specialized and ultimately losing their ecological niche to others. It also shows researchers how life responds to a mass extinction event, which in this case was the mother of all extinction events, immediately after the event itself.

Although this particular species of ichthyosauriform went extinct soon after it evolved, it beautifully showcases the types of aquatic features that natural selection deemed to be appropriate at a time of huge environmental change. Ultimately, though, this fossil raises more questions than it answers, most prominently of all being this: How was this line of marine reptiles able to evolve so incredibly quickly right after life on Earth almost ended?

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Read more: http://www.iflscience.com/plants-and-animals/peculiar-ancient-marine-reptile-reveals-life-evolved-rapidly-after-great-dying