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Behind-the-Scenes: New best friends, Bruno Braga and Emma Oreck-Pope snooze in the COSMOS New Mexico production offices.
-Sarah Mozal, Assistant to Ann Druyan and Mitchell Cannold
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Jurassic Predators Had Surprisingly Sensitive Snouts
by Jeff Hecht
Pliosaurs had massive jaws, crushing teeth – and sensitive snouts. That is the conclusion of a study on an exceptionally preserved 2-metre-long fossil skull.
Pliosaurs were the top marine predators of the Jurassic, growing up to 12 metres long, but their biology is poorly understood because nothing quite like them is alive today.
Davide Foffa at the University of Bristol, UK, may now have added an important piece to the puzzle of how they detected prey. He has found channels in a pliosaur skull that probably contained nerves and blood vessels, suggesting that it had a well-developed sensory system extending to the tip of the snout.
Palaeontologists have long recognised that pliosaur skulls, like those of many other vertebrates, have small holes called foramina leading into the interior. In living species these connect to nerves. However, this is the first time anyone has been able to trace the networks inside a fossil…
(read more: New Scientist)
illustration by Dmitry Bogdanov
9:58pm (323 notas)
This year marks the centenary of the beginning of the First World War. Oxford University Press is sharing numerous resources for scholars and students looking for new understanding of the war and its legacy: the physical trauma of the war and the rapid changes in the medical field in the…
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Happy birthday to Carl Akeley, born 150 years ago today.
Explorer and Museum taxidermist, Akeley is remembered for his pioneering method of taxidermy, combining field observations with sculptural techniques, and for his contributions to the iconic Museum hall that bears his name: The Akeley Hall of African Mammals.
Akeley is also remembered for his contributions to conservation. In the course of researching and collecting specimens to create the now-famous mountain gorilla diorama, he was among the first to accurately document mountain gorillas as intelligent and social animals that, even then, were under grave threat from overhunting. His research inspired him to dedicate the last few years of his life to the conservation and protection of the mountain gorilla.
We humans have been around for about 2.5 million years, but the beating of our hearts is controlled by something much older than Homo sapiens—an ancient molecular pathway that, according to Huck Institutes faculty researcher Tim Jegla, may be on the order of 700 million to a billion years old. The Jegla Lab studies the evolution of the nervous and muscular systems, using model organisms such as the cnidarian Nematostella vectensis—also known as the starlet sea anemone—to investigate conserved traits and the molecular pathways and genes that underpin them. According to Jegla, the starlet sea anemone is in essence an animal that’s as evolutionarily far away from humans as possible while still sharing the same neuromuscular signaling systems. Comparisons of humans and cnidarians reveal that only the fundamentally important mechanisms are conserved—such as those required to make a neuron or, in this case, a neuromuscular signal. “Basically,” he says, “when we compare a human and a sea anemone, we’re looking at somewhere between 700 million and a billion years’ evolutionary separation. Anything that’s not fundamentally critical to life as a mobile, multicellular animal is different. And the things we have in common were there in the nervous system of the animal we both evolved from; they were there in the ancestor of virtually all modern animal life other than sponges and comb jellies. Only the fundamental mechanisms are conserved. And this gives us a window into what things we have in common that are extremely important. It tells us a lot about the history of how animals evolved.” “We make the case in this paper,” Jegla continues, “that the properties of the human Erg channel and the ancient Nematostella channel are tuned extremely well to repolarize the long action potentials that you need to get a strong muscular contraction, or a prolonged wave contraction like you have in a heartbeat.
In a study recently published in Proceedings of the National Academy of Sciences, the Jegla Lab identified in the Nematostella sea anemone the same gene family (Erg) that is responsible for the slow-wave contractions of the human heart. After cloning the genes for further investigation, the researchers found that the ion channel it encodes has retained its function relatively unchanged since the time of humans’ and cnidarians’ divergence from their common ancestor almost a billion years ago.
"This discovery," says Jegla, "shows that at least some of the molecular mechanisms through which we control electrical activity in things like the heart evolved in some of the earliest animals, long before the existence of hearts or even cardiac tissue."
"This fits a broad pattern we’re finding," Jegla continues, "that almost all the major signaling systems used in our brains and muscles evolved hundreds of millions of years ago in an ancestor of bilaterians which seems to have had a very versatile and molecularly complete set of tools for neuronal function that has been conserved throughout subsequent animal evolution and tuned to the specific needs of the major animal phyla. It appears that a lot of the signaling that we do in our complex neuromuscular systems is based on pre-existing programs that are just adapted to our specific physiological needs.""
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Another one from me at Wired:
The Internet of Things is coming. And the tech cognoscenti aren’t sure that’s a good thing.
For years, the prospect of an online world that extends beyond computers, phones, and tablets and into wearables, thermostats, and other devices has…