Extinct early whales listened like their relatives on land, fossil evidence shows

June 8, 2017

Whales rely on a keen sense of hearing for their underwater existence. But whales show surprisingly vast differences in hearing ability. Baleen whales tune into infrasonic sounds—at frequencies too low for humans to hear—to communicate over long distances. Toothed whales do just the opposite, relying on ultrasonic frequencies too high for humans to hear.

Now researchers reporting in Current Biology on June 8 have fossil evidence from extinct early whale species to suggest that those differences in hearing arose only after whales evolved into the fully aquatic animals we know today. That's based on their findings that whales known as protocetes, which spent time both in water and on land, appear to have hearing more like their terrestrial, even-toed ungulate relatives, including pigs, hippos, and camels.

"We found that the cochlea of protocetes was distinct from that of extant whales and dolphins and that they had hearing capacities close to those of their terrestrial relatives," says Maeva Orliac of CNRS and Université de Montpellier in France.

Protocetes' lack of hearing specialization suggests that the early whales were unable to echolocate and communicate through long-distance calls in the way that modern-day cetaceans, the group including whales and dolphins, do.

The researchers came to those conclusions based on studies of 45-million-year-old protocetid whale remains found in marine deposits from Togo in West Africa. The researchers studied the bony labyrinth, a hollow cavity that would have housed the hearing organ, in two species of early whales.

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How the mouse came to live alongside humans

By Helen Briggs BBC News

28 March 2017

Mice have been living alongside humans for 15,000 years, according to fossil evidence.

This is earlier than previously thought - and predates the dawn of agriculture.

Scientists believe wild mice crept into settlements in the Levant (Eastern Mediterranean) region to steal wild grains and seeds that ancient people had gathered and stored.

The rodents became what we know today as house mice, enjoying free food and shelter in human homes. 

"Nowadays, thanks to this relationship, house mice have colonised almost every corner of the globe to become almost as ubiquitous as humans and also one of the most invasive mammalian species," said Dr Thomas Cucchi of Museum national d'Histoire naturelle, Paris.

His research is based on studies of teeth from the remains of rodents found in the southern Levant. 

Mice started their relationship with humans "as soon as our species started to stay put and build houses 15,000 years ago", he said.

The people lived in round houses made of stone and mud. They foraged for wild cereals, such as emmer wheat and barley, and hunted deer and wild boar.

Mice appear to have thrived in this environment, with ample food to eat and few predators. It was a while before cats and dogs arrived on the scene. 

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'The Yeti may be real' Sir David Attenborough claims legendary beast does exist!

The veteran broadcaster is convinced fossil evidence found in the 1930s proves a 10-12ft tall animal lived in the region.

Speaking to Jarvis Cocker at a UKTV 2013-2014 Showcase, Sir David, 87, said he had not given up hope of the creature being real.

He said: "I believe the Abominable Snowman may be real. I think there may be something in that.

"A fossil was found with these huge molars that are four of five times the size of human molars."

Sir David said that the Himalayan forests which cover over 14,000 square miles could easily contain a Yeti.

"If there are some still alive and you walked near their habitat you can bet that these creatures may be aware of you, but you wouldn't be aware of them," he added.

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Tuna Closely Related to Some of the Strangest Fish in the Sea

Sep. 13, 2013 — Some of the strangest fish in the sea are closely related to dinner table favourites the tunas and mackerels, an international team including Oxford University scientists has found.

Deep sea fish such as the black swallower, with an extendable stomach that enables it to eat fish larger than itself, and manefishes, some sporting spiky fins like a Mohican haircut, are close cousins to mackerels and tuna despite having completely different body shapes and lifestyles.

The team, led by Dr Masaki Miya at Chiba Natural History Museum in Japan, suggests that this extended family of fishes might owe its success today to the devastating extinction that marked the demise of dinosaurs and many other creatures 66 million years ago.

The researchers report in the journal PLOS ONE this week how they combined DNA analysis of over 5,000 modern fish species with fossil evidence to solve the mystery of which species were closest to tunas and mackerels in the fish family tree.

'What was immediately clear from our result is that the extended family of tunas and mackerels is made up of fishes that all look very different from one another, with different ways of life, but which share one key trait: they all dwell in the open ocean,' said Dr Miya of Chiba Natural History Museum. 'This had been suggested before, but we were able to show that many additional groups of fishes inhabiting the open ocean -- called the pelagic realm -- were closely related to one another and to tunas.'

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Earliest placental mammal ancestor pinpointed

By Jason PalmerScience and technology reporter, BBC News

The creature that gave rise to all the placental mammals - a huge group that includes whales, elephants, dogs, bats and us - has at last been pinpointed.

An international effort mapped out thousands of physical traits and genetic clues to trace the lineage.

Their results indicate that all placental mammals arose from a small, furry, insect-eating animal.

A report in Science resolves the debate as to when the creature lived; it came about after the demise of dinosaurs.

That had been a hotly debated question over years of research.

Placental mammals - as opposed to the kind that lay eggs, such as the platypus, or carry young in pouches, such as the kangaroo - are an extraordinarily diverse group of animals with more than 5,000 species today. They include examples that fly, swim and run, and range in weight from a couple of grams to hundreds of tonnes.

A wealth of fossil evidence had pointed to the notion that the group, or clade, grew in an "explosion" of species shortly after the dinosaurs' end about 65 million years ago.

Continued:  http://www.bbc.co.uk/news/science-environment-21350900#