The Biology, Agriculture, and Paleontology thread

South Africa's Great Karoo reveals mass extinction: "Scientists have obtained an age from rocks of the Great Karoo that shed light on the timing of a mass extinction event that occurred around 260 million years ago."

Spectacular Moroccan fossils redefine evolutionary timelines: "Some of the oldest marine animals on the planet, including armoured worm-like forms and giant, lobster like sea creatures, survived millions of years longer than previously thought, according to a spectacularly preserved fossil formation from southeastern Morocco."

Brawling badgers age faster: "Male badgers that spend their youth fighting tend to age more quickly than their passive counterparts according to new research. The 35-year study revealed that male badgers living alongside a high density of other males grow old more quickly than those living with lower densities of males."

First images of dolphin brain circuitry hint at how they sense sound: "A novel DTI technique used on the preserved brains of two dolphins that died after stranding shows that at least two areas of the dolphin brain are associated with the auditory system, unlike most mammals that primarily process sound in a single area."

New research uncovers brain circuit in fruit fly that detects anti-aphrodisiac: "New research, published today in eLife, identified the neural circuit in the brain of the fruitfly (Drosophila melanogaster) that is responsible for detecting a taste pheromone, which controls the decision of male flies to mate with females."

Carnivorous plant's sound echoes draw bats in

South African archaeological wonder-sites reveal more of the origins of our unity and diversity: "Two of South Africa's most famous archaeological sites, Sibudu and Blombos, have revealed that Middle Stone Age groups who lived in these different areas, more than 1,000 km apart, used similar types of stone tools some 71,000 years ago, but that there were differences in the ways that these tools were made .But this was not the case at 65,000 years ago when similarities in stone tool making suggest that similar cultural traditions spread across South Africa."

Early jellyfish-like creatures sported armor: "Today, sea creatures known as comb jellies have soft bodies like jellyfish, but their ancestors projected a tougher image: tooling up with hard body parts, probably as protection from predators. In a new analysis of fossils, researchers looked closely at more than three dozen specimens from 520-million-year-old rocks in southern China. Like their modern-day relatives, the ancient creatures had saclike bodies and propelled themselves through the water using eight rows of hairlike structures called cilia. But the ancient species—three that are new to science and three that were previously known but are now being more fully described based on the new analysis—also included eight stiff struts (depicted in white in the artist’s reconstructions above) and eight rigid plates that surrounded a buoyancy-sensing organ called a statolith."

Male black widow spiders destroy female’s web to deter rivals: "Male black widow spiders destroy large sections of the female's web during courtship and wrap it up in their own silk. New research shows that this home-wrecking behavior deters rival males, by making the female's web less attractive to them. Surprisingly, the females don't seem to mind the destruction. The authors of the study say the males' behavior could protect the female from harassment, enabling her to get on with parenting."

Tiny genetic tweak unlocked corn kernels during domestication: "If not for a single genetic mutation, each kernel on a juicy corn cob would be trapped inside a inedible casing as tough as a walnut shell. The mutation switches one amino acid for another at a specific position in a protein regulating formation of these shells in modern corn's wild ancestor, according to a new study."

Worms hitch rides on slugs when traveling to far flung places: "Slugs and other invertebrates provide essential public transport for small worms in the search for food, according to new research."

Advanced composites may borrow designs from deep-sea shrimp: "New research is revealing details about how the exoskeleton of a certain type of deep-sea shrimp allows the animal to survive scalding hot waters in hydrothermal vents thousands of feet under water. Insights into the complex molecular behavior of the materials could have implications for the design of new synthetic armor capable of withstanding environmental extremes."

With teeth like that, this pre-dinosaur vegetarian was no push over: "Head-butting and canine display during male-male combat first appeared some 270 million years ago. This is what researchers found when they conducted an updated in-depth study of the herbivorous mammalian ancestor, Tiarajudens eccentricus, discovered four years ago."

Scientists ‘watch’ rats string memories together: "By using electrode implants to track nerve cells firing in the brains of rats as they plan where to go next, scientists say they have learned that the mammalian brain likely reconstructs memories in a way more like jumping across stepping stones than walking across a bridge. The research sheds light on what memories are and how they form, and gives clues about how the system can fail."

Watch: How scientists brought an extinct frog back to life: "We all know by now that, sadly, a Jurassic Park-like dinosaur restoration is pretty unlikely. But, in 2013, Australian scientists did manage to bring an extinct species of frog back to life - albeit temporarily. And now they're hoping to do so more permanently in the future, as the latest episode of the University of New South Wales' (UNSW) 'Catastrophic Science' explains.

So what's so special about the amphibian? The gastric brooding frog was first discovered in the 1970s, when scientists realised it had a pretty fascinating reproductive strategy. Instead of letting its offspring develop in the water, the species swallows its fertilised eggs or newly hatched tadpoles, and turns its stomach into a uterus where they develop until they're fully formed frogs. When they're ready to leave the womb, the gastric brooding frog will projectile vomit its offspring out into the world. Yep, projectile vomits.

As gross as that sounds, the strategy got scientists pretty excited about all the incredible things they could learn from the species, such as new fertility strategies and treatments for stomach conditions such as ulcers.

But by the early '80s, the gastric brooding frog was driven to extinction by an introduced species of fungus, and the work was lost. Now an international team involving UNSW scientists is hoping to reverse that."

Smart cornfields of the future: "Scientists have slipped the leash of scientific caution and tried to imagine what they would do if they could redesign plants at will. The ideas they dreamed up may make the difference between full bellies and empty ones in the near future when population may outrun the ability of traditional plant breeding to increase yields."

Evolution of our mammalian ancestor's ear bone detailed: "The first detailed and comprehensive analysis on the ear bone of Triassic cynodonts has completed, and researchers have found some noticeable variations in the morphology of this bone — even among animals of the same species."

50 million year old sperm cells found in fossilized cocoon: "A small team of researchers with members from institutions in Sweden, Argentina and Italy, has discovered fossilized sperm cells embedded in the walls of an ancient cocoon. In their paper published in the journal Biology Letters, the group describes how they came across the sperm fossils while studying a 50 million year old cocoon found on Seymour Island in Antarctica."

'Speed cells' in brain track how fast animals run: "Glance at a runner's wrist or smartphone, and you'll likely find a GPS-enabled app or gadget ticking off miles and minutes as she tries to break her personal record. Long before FitBit or MapMyRun, however, the brain evolved its own system for tracking where we go. Now, scientists have discovered a key component of this ancient navigational system in rats: a group of neurons called "speed cells" that alter their firing rates with the pace at which the rodents run. The findings may help explain how the brain maintains a constantly updated map of our surroundings."

How birds learn foreign languages: "Biologists have succeeded in teaching wild birds to understand a new language. After only two days of training, fairy wrens learned to flee when they heard an alarm call that was foreign to them, showing that birds can learn to eavesdrop on the calls of other species."

Jurassic saw fastest mammal evolution: "Mammals were evolving up to 10 times faster in the middle of the Jurassic than they were at the end of the period, coinciding with an explosion of new adaptations, new research shows."

The mosquito smells, before it sees, a bloody feast: "The itchy marks left by the punctured bite of a mosquito are more than pesky, unwelcomed mementos of a day at the lake. These aggravating bites can also be conduits for hitchhiking pathogens to worm their way into our bodies. Mosquitoes spread malaria, dengue, yellow fever and West Nile virus, among others. As the bloodsucking insects evolve to resist our best pesticides, mosquito control may shift more to understanding how the mosquitoes find a tasty — and unsuspecting — human host. A team of biologists has now cracked the cues mosquitoes use to find human hosts."

Scientist develops model for robots with bacteria-controlled brains: "Forget the Vulcan mind-meld of the Star Trek generation—as far as mind control techniques go, bacteria is the next frontier.

In a paper published July 16 in Scientific Reports, which is part of the Nature Publishing Group, a Virginia Tech scientist used a mathematical model to demonstrate that bacteria can control the behavior of an inanimate device like a robot."

'Big Bird' dino: Researchers discover largest ever winged dinosaur: "When we see birds winging their way across the sky, we are really looking at living dinosaurs—the only lineage of these mighty beasts that survived mass extinction. Yet before they went extinct, many dinosaurs sprouted wings themselves. Researchers now report finding the largest ever winged dino in China, a sleek, birdlike creature adorned with multiple layers of feathers all over its arms and torso that lived 125 million years ago. It almost certainly could not fly, however—an important confirmation that wings and feathers originally evolved to serve other functions like attracting mates and keeping eggs warm."

Plant defense hormones help sculpt root microbiome: "According to new research, the defense hormone salicylic acid helps select which bacteria live both inside and on the surface of a plant's roots, keeping some bacteria out and actively recruiting others."

Genetically modified moths pass greenhouse testing, ready for the wild: "A team of researchers at British company Oxitec has developed a genetic approach to controlling diamondback moth caterpillars and report that trials in greenhouse conditions has gone so well that they are ready to conduct tests in the wild. In their paper published in the journal BMC Biology, the team describes their technique, how it works, how safe they believe it is and their hopes that their efforts will lead to reduced crop destruction by the caterpillars."

edited 21st Jul '15 1:51:50 AM by rmctagg09

Finding the origins of life in a drying puddle: "Anyone who's ever noticed a water puddle drying in the sun has seen an environment that may have driven the type of chemical reactions that scientists believe were critical to the formation of life on the early Earth."

Rare form: Novel structures built from DNA emerge: "Scientists have worked for many years to refine the technique of DNA origami. His aim is to compose new sets of design rules, vastly expanding the range of nanoscale architectures generated by the method. In new research, a variety of innovative nanoforms are described, each displaying unprecedented design control."

Ancient life in three dimensions: "Hidden secrets about life in Somerset 190 million years ago have been revealed in a new study of some remarkable fossils. Thanks to exceptional conditions of preservation, a whole marine ecosystem has been uncovered — and yet it was already known 150 years ago."

I hope this belongs here. Either way:

Links I can find about it In english detail more about the genetic correlation between the native american population and the old world.

Spanish here

edited 22nd Jul '15 10:06:54 AM by Aszur

New evidence of cultural diversification between neighboring chimpanzee communities: "Newly discovered tool-length 'subcultures' in our closest living relatives provide striking parallel with cultural differences observed between adjacent groups in human societies."

First evidence of farming in Mideast 23,000 years ago: "Until now, researchers believed farming was 'invented' some 12,000 years ago in an area that was home to some of the earliest known human civilizations. A new discovery offers the first evidence that trial plant cultivation began far earlier — some 23,000 years ago."

Resolving social conflict is key to survival of bacterial communities: "Far from being selfish organisms whose sole purpose is to maximize their own reproduction, bacteria in large communities work for the greater good by resolving a social conflict among individuals to enhance the survival of their entire community."

Kiwi bird genome sequenced: "Its unusual biological characteristics make the flightless kiwi a unique kind of bird. Researchers of the University of Leipzig and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have now sequenced the genetic code of this endangered species and have identified several sequence changes that underlie the kiwi's adaptation to a nocturnal lifestyle: They found several genes involved in colour vision to be inactivated and the diversity of odorant receptors to be higher than in other birds - suggesting an increased reliance on their sense of smell rather than vision for foraging. The study was published in the journal Genome Biology."

Small oxygen jump in atmosphere helped enable animals take first breaths: "Measurements of iron speciation in ancient rocks were used to construct the chemistry of ancient oceans. Analysis suggests that it took less oxygen than previously thought to trigger the appearance of complicated life forms."

Stressed young birds stop learning from their parents and turn to wider flock: "Juvenile zebra finches that experience high stress levels will ignore how their own parents forage and instead learn such skills from other, unrelated adults. This may help young birds avoid inheriting a poor skillset from parents — the likely natural cause of their stress — and becoming trapped by a 'bad start in life.'"

Female stink bugs 'select' color of their eggs: "Stink bug mothers will lay darker or lighter eggs depending on how much light is reflecting off of a surface. The newly discovered adaptation is likely related to how some species of stink bugs are able to deposit their eggs on top of leaves, as the darker-colored eggs are better protected from UV radiation. Surprisingly, the eggs are not darkened by melanin, but by a previously unknown pigment."

Four-legged snake fossil stuns scientists—and ignites controversy: "Scientists have described what they say is the first known fossil of a four-legged snake. The limbs of the 120-or-so-million-year-old, 20-centimeter-long creature are remarkably well preserved and end with five slender digits that appear to have been functional. Thought to have come from Brazil, the fossil would be one of the earliest snakes found, suggesting that the group evolved from terrestrial precursors in Gondwana, the southern remnant of the supercontinent Pangaea. But although the creature’s overall body plan—and indeed, many of its individual anatomical features—is snakelike, some researchers aren’t so sure that it is a part of the snake family tree."

edited 23rd Jul '15 5:16:06 PM by rmctagg09

Bossy rooster takes lead vocal of cock-a-doodle-do: "From ancient times, people have been aware of the rooster's "cock-a-doodle-do" that marks the break of dawn, but has anyone wondered who crows first? In a new study, biologists have revealed that there is actually a systematic rule based on social ranking that determines the order of crowing in roosters."

Mammoths killed by abrupt climate change: "New research has revealed abrupt warming, that closely resembles the rapid man-made warming occurring today, has repeatedly played a key role in mass extinction events of large animals, the megafauna, in Earth's past."

Boa Constrictors Don't Actually Suffocate Their Prey To Death After All: "The idea of suffocating in the grip of a boa constrictor's coils is enough to make anyone gasp for breath with worry. However, some keen-eyed researchers thought that suffocation might not be the true cause of death from a boa constrictor. Instead, it was found that boa constrictors do just that: constrict their prey to death."

And by constrict, we mean constricting blood and potassium ion flow rather than airflow.

Got a request to rename this thread to "The Biology, Agriculture, and Paleontology thread". Is there any disagreement?

Well, nobody commented in opposition when the topic was brought up here.

My vote hasn't changed.

Why the Y in polar bears matters: For the first time, essential parts of the polar bear Y chromosome have been decoded: "For the first time, scientists have reconstructed part of the male chromosome in polar bears. The scientists were able to assign 1.9 million base pairs specifically to the polar bear Y chromosome.They now show that more than 100,000 years ago, the male polar bear lineages split and developed in two separate genetic groups."

Plant light sensors came from ancient algae: "The light-sensing molecules that tell plants whether to germinate, when to flower and which direction to grow to seek more sunlight were inherited millions of years ago from ancient algae, finds a new study. The findings are some of the strongest evidence yet against the prevailing idea that the ancestors of early plants got the red light sensors that helped them move from water to land by engulfing bacteria, the researchers say."

Origins of life: New model may explain emergence of self-replication on early Earth: "One question of the origin of life in particular remains problematic: what enabled the leap from a primordial soup of individual monomers to self-replicating polymer chains? A new model proposes a potential mechanism by which self-replication could have emerged. It posits that template-assisted ligation, the joining of two polymers by using a third, longer one as a template, could have enabled polymers to become self-replicating."

Unique tooth structure allowed predatory dinosaurs to efficiently crunch flesh and bone: "The Tyrannosaurus rex and its fellow theropod dinosaurs that rampage across the screen in movies like Jurassic World were successful predators partly due to a unique, deeply serrated tooth structure that allowed them to easily tear through the flesh and bone of other dinosaurs, says new research from the University of Toronto Mississauga (UTM).

The research, published in the journal Scientific Reports, was conducted by Kirstin Brink, a post-doctoral researcher in the Department of Biology at UTM; Professor Robert Reisz of the Department of Biology and the UTM vice-principal of graduate studies; and colleagues at the Royal Ontario Museum (ROM) and the National Synchrotron Radiation Research Center in Taiwan."

Ancient lizards in amber amaze scientists: "A community of lizards from the Caribbean, preserved for 20 million years in amber, have been found to be identical to their modern cousins, say researchers.

This suggests the different niches inhabited by the lizards have - incredibly - changed little over the past 20 million-year, report the team, in this week's Proceedings of the National Academy of Sciences."

edited 28th Jul '15 7:03:08 PM by rmctagg09

That thing about the lizards not changing will surely delight creationists who insist that evolution isn't true. Of course they'll still have a problem with the age of the sample - which they'll explain away by claiming that radiometric dating doesn't work - but I have no doubt that I'll be seeing distorted references to this discovery in the next year or two in creationist propaganda.

I'm just glad I'm an evolutionary creationist (aka theistic evolutionist).

Have you noticed every pop culture source on T. rex refers to it having serrated cutting teeth when it didn't? Tom Holtz himself confirms this.

Stressed out plants send animal-like signals: "For the first time, research has shown that, despite not having a nervous system, plants use signals normally associated with animals when they encounter stress."

Chimpanzees binge on clay to detox and boost the minerals in their diet: "Wild chimpanzees in the forests of Uganda are increasingly eating clay to supplement the minerals in their diet, according to a long-term international study . The article describes how the researchers observed wild chimpanzees in the Budongo forest eating and drinking from clay pits and termite mounds."

Watch: Divers in Turkey stumble across a gelatinous blob the size of a car: "In case you haven't heard, the ocean is filled with a whole bunch of weird things, and also very large things. We've got Japanese spider crabs (Macrocheira kaempferi) with legs that stretch over 3.7 metres long. Giant clams (Tridacna gigas) with shells that grow to 1.3 metres long. Even humble jellies can break records, with the Lion's mane jellyfish (Cyanea capillata) rumoured to have tentacles that are over 36 metres long. But what divers discovered off the coast of Turkey recently is that not only does ocean life come in massive proportions, the egg clusters they spawn from can be super-sized too."

Really? I haven't noticed. And a quick google search turned up a BBC article citing at least one paeleontologist that seems to indicate that you might be wrong about them not having serrated teeth.

Erm, could you paraphrase? Because I can readily see a serrated striation in every single Tyrannosaurid teeth photo I can find.

edited 29th Jul '15 7:11:41 PM by Eriorguez

... I didn't say they were saying they did not have serrated teeth. I said they were saying that they did have them.