The Biology, Agriculture, and Paleontology thread

Secrets of the seahorse tail revealed: "A team of engineers and biologists reports new progress in using computer modeling and 3D shape analysis to understand how the unique grasping tails of seahorses evolved. These prehensile tails combine the seemingly contradictory characteristics of flexibility and rigidity, and knowing how seahorses accomplish this feat could help engineers create devices that are both flexible and strong."

What 300,000 year old eggshells reveal about the environment of the Paleolithic: "In the 1990s the discovery of the oldest human made and completely preserved wooden hunting weapons made the Paleolithic excavation site in Schoningen internationally renowned. Contained within the 300,000 year-old deposits on a former lake shore in what is now Lower Saxony organic materials remain extremely well preserved, including eggshells that scientists were able to identify as eggshell remains from various species of birds."

Mice sing like songbirds to woo mates: "Male mice sing ultrasonic vocalizations beyond human hearing to seduce females, according to a new study. The male's loud, more complex hailing song is replaced by a softer, simpler song when the female is near. Researchers developed a new statistical method for analyzing song patterns in mice, because the animals may be useful in research on human communication disorders."

Oxygen-depleted toxic oceans had key role in mass extinction over 200 million years ago: "Changes in the biochemical balance of the ocean were a crucial factor in the end-Triassic mass extinction, during which half of all plant, animal and marine life on Earth perished, according to new research."

Worm lizards dispersed by 'rafting' over oceans, not continental drift: "Tiny, burrowing reptiles known as worm lizards became widespread long after the breakup of the continents, leading scientists to conclude that they must have dispersed by rafting across oceans soon after the extinction of the dinosaurs, rather than by continental drift as previously thought."

Tiny songbird discovered to migrate non-stop, 1,500 miles over the Atlantic: "For the first time biologists report 'irrefutable evidence' that tiny blackpoll warblers complete a nonstop flight from about 1,410 to 1,721 miles (2,270 to 2,770 km) in just two to three days. For this work the scientists fitted geolocator packs on 20 birds in Vermont and 20 more in Nova Scotia. They were able to recapture three birds from the Vermont group and two from the Nova Scotia group for analyses."

New instrument dates old skeleton before 'Lucy'; 'Little Foot' 3.67 million years old: "A skeleton named Little Foot is among the oldest hominid skeletons ever dated at 3.67 million years old, according to an advanced dating method. Little Foot is a rare, nearly complete skeleton of Australopithecus first discovered 21 years ago in a cave at Sterkfontein, in central South Africa. Stone tools found at a different level of the Sterkfontein cave also were dated at 2.18 million years old, making them among the oldest known stone tools in South Africa."

Ants' intruder defense strategy could lead to better email spam filters, biologist finds: "To kill spam, email filters might need to act a bit more like ants.

Deborah M. Gordon, a biology professor at Stanford, has worked with a computer scientist, Fernando Esponda, and produced a model that suggests that ant colony defense behavior follows the same distributed network rules as the human immune system. The work suggests that evolution has twice produced a simple security protocol for social insects that, installed in email servers, could make them far more difficult for spammers to hack."

Algae from wastewater solves two problems: "In one of the first studies to examine the potential for using municipal wastewater as a feedstock for algae-based biofuels, Rice University scientists found they could easily grow high-value strains of oil-rich algae while simultaneously removing more than 90 percent of nitrates and more than 50 percent of phosphorous from wastewater."

Cost of lab-grown burger patty drops from $325,000 to $11.36: "Back in 2013, ‘test-tube’ hamburgers hit headlines across the Internet, and not just because scientists had managed to more-or-less replicate meat in the lab. It was a commendable feat, especially because it offered a potential solution to the increasingly unsustainable practice of cattle farming, but then we heard about the price tag. Who’s up for a $325K burger made from cultured muscle tissue cells? Anyone? Last chance? You sure?

But just two years on, and scientists have announced a drastic cut in the cost of producing one of these patties, saying the price tag is now just a little more than $11 per burger, or $80 per kilogram of the meat. And the best part? The technique requires just a just a small piece of muscle to produce 10,000 kilos of lab meat."

So another couple years and it might be economically competitive? That would be nice.

How Europeans evolved white skin: "Most of us think of Europe as the ancestral home of white people. But a new study shows that pale skin, as well as other traits such as tallness and the ability to digest milk as adults, arrived in most of the continent relatively recently. The work, presented here last week at the 84th annual meeting of the American Association of Physical Anthropologists, offers dramatic evidence of recent evolution in Europe and shows that most modern Europeans don’t look much like those of 8000 years ago."

Producing strawberries in high-pH soil at high elevations: "Fruit and vegetable production in high-elevation areas can be a difficult enterprise. Variable weather and soil conditions typical of these regions, such as the southwestern United States, present multiple challenges for growers. 'High frequency and intensity of late spring frosts in semiarid climates have made fruit production challenging,' explained Shengrui Yao, corresponding author of a study in the February 2015 issue of HortScience. 'Growers may only harvest five to six apple crops during a 10-year period, and, as a result, many are forced to abandon their orchards.' To lessen the negative impacts of unreliable weather and soil conditions, growers in the region are looking to alternative crops to help them stay in business. Yao and researchers Steve Guldan, Robert Flynn, and Carlos Ochoa studied multiple strawberry varieties, and found some promising options for growers in the U.S. Southwest."

Sea sponge anchors are natural models of strength: "Life may seem precarious for the sea sponge known as Venus' flower basket. Tiny, hair-like appendages made essentially of glass are all that hold the creatures to their seafloor homes. But fear not for these creatures of the deep. Those tiny lifelines, called basalia spicules, are fine-tuned for strength, according to new research led by Brown University engineers.

In a paper published in the Proceedings of the National Academy of Sciences, the researchers show that the secret to spicules' strength lies in their remarkable internal structure. The spicules, each only 50 microns in diameter, are made of a silica (glass) core surrounded by 10 to 50 concentric cylinders of glass, each separated by an ultra-thin layer of an organic material. The walls of each cylinder gradually decrease in thickness moving from the core toward the outside edge of the spicule."

Brontosaurus is back! Brontosaurus is a unique genus after all: "Although well known as one of the most iconic dinosaurs, Brontosaurus (the 'thunder lizard') has long been considered misclassified. Since 1903, the scientific community has believed that the genus Brontosaurus was in fact the Apatosaurus. Now, an exhaustive new study by palaeontologists from Portugal and the UK provides conclusive evidence that Brontosaurus is distinct from Apatosaurus and as such can now be reinstated as its own unique genus."

Gotcha! Ultra-realistic robot proves there's more than one way to scare a fish: "In the world of the tiny zebrafish, the predatory red tiger oscar is the stuff of nightmares. And while the species has no natural reason to fear robots, researchers at the NYU Polytechnic School of Engineering have published the first study showing that, in a side-by-side comparison, a robotic predator can spook zebrafish just as well as the real thing. Their results may help advance understanding of fear and anxiety in animal populations, including humans."

Two ancient human fossils from Laos reveal early human diversity: "An ancient human skull and a jawbone found a few meters apart in a cave in northern Laos add to the evidence that early modern humans were physically quite diverse, researchers report. The skull has fully modern features while the jaw is a mix of modern and archaic traits."

New evidence for combat and cannibalism in tyrannosaurs: "A new study documents injuries inflicted in life and death to a large tyrannosaurine dinosaur. The paper shows that the skull of a tyrannosaur genus, Daspletosaurus, suffered numerous injuries during life, at least some of which were likely inflicted by another Daspletosaurus. It was also bitten after death in an apparent event of scavenging by another tyrannosaur. Thus there's evidence of combat between two large carnivores as well as one feeding on another after death."

Greatest mass extinction driven by acidic oceans, study finds: "Changes to the Earth's oceans, caused by extreme volcanic activity, triggered the greatest extinction of all time, a study suggests. The amount of carbon added to the atmosphere that triggered the mass extinction was probably greater than today's fossil fuel reserves, the team says. However, the carbon was released at a rate similar to modern emissions. This fast rate of release was a critical factor driving ocean acidification, researchers say."

Mountain gorillas: Lots of deleterious genetic variation disappeared from population thanks to inbreeding: "Researchers have produced the first whole-genome sequences of endangered mountain gorillas in the Virunga volcanic mountain range in central Africa. Findings from sequence analysis suggest the gorillas have lived in small groups for thousands of years, coping well with inbreeding that scientists feared would lead to health problems. Based on these results, scientist say the gorillas, if properly protected from habitat destruction and hunting, should continue to flourish for thousands of years to come."

... Inbreeding without accumulating genetic defects? I bet all the eugenicists and pro-incest activists in the world would be tripping over themselves to unlock the secret to that.

Panama debate fueled by zircon dating: "New evidence by geologists dates the closure of an ancient seaway at 13 to 15 million years ago and challenges accepted theories about the rise of the Isthmus of Panama and its impact on world climate and animal migrations."

New species of 'terror bird' discovered: "Famed for their large hooked beaks and a presumed taste for meat, flightless phorusrhacids, also known as 'terror birds,' were among South America’s top predators before going extinct about 2.5 million years ago. Now paleontologists have unearthed one of the most complete fossils of a phorusrhacid to date. The skeleton of the new species, dubbed Llallawavis scagliai, is approximately 95% complete, giving scientists the ability to study a terror bird’s anatomy in unprecedented detail. Analyses of the well-preserved remains are already providing insights into the bird’s hearing ability, scientists say."

Ocean myth busted: 'Toddler' sea turtles are very active swimmers: "It turns out sea turtles, even at a tender 6-18 months of age, are very active swimmers. They don't just passively drift in ocean currents as researchers once thought. Researchers say it's an important new clue in the sea turtle 'lost years' mystery. Where exactly turtles travel in their first years of life, before returning to coastal areas as adults to forage and reproduce, has puzzled scientists for decades."

Vampire bats have a taste for bacon: "Examining animal droppings is not glamorous—even if you’re studying vampires. But, for scientists interested in the diet of the common vampire bat (Desmodus rotundus), it’s one of the few ways to learn what they eat. In a new study, researchers used DNA found in the bats’ feces to learn whose blood they suck and which blood they like best. The team discovered that although chicken DNA was most frequently found, it’s pigs that the bats seem to crave."

About the Brontosaurus/Apatosaurus deal: A merely subjective issue such as what is a genus cannot get "conclussive proof". Each worker has their own "genericometer" after all (however, the one in this study is finely tuned to avoid double standards). And Apatosaurus (a genus with 2 species) and Brontosaurus (with 3 species) end up as each other's closest relative, so a single genus with 5 species wouldn't be more right or more wrong.

The paper is also 299 pages long, and is a very in-depth analysis of Diplodocids (a per specimen study). It is a damn shame the focus goes to a subjective matter, when the sheer ammount of data that went there is far more important and gamechanging that having an A. or a B. before excelsus (seriously, Supersaurus as a Diplodocine instead of as an Apatosaurine was very unexpected).

You have a point there, in comparison Brontosaurus getting genus status back is a mere pittance.

A new beginning for baby mosasaurs: "They weren't in the delivery room, but researchers at Yale University and the University of Toronto have discovered a new birth story for a gigantic marine lizard that once roamed the oceans.

Thanks to recently identified specimens at the Yale Peabody Museum of Natural History, paleontologists now believe that mighty mosasaurs—which could grow to 50 feet long—gave birth to their young in the open ocean, not on or near shore.

The findings answer long-held questions about the initial environment of an iconic predator that lived during the time of the dinosaurs. Mosasaurs populated most waters of the Earth before their extinction 65 million years ago."

Viviparity is quite common in squamatans, so the giant seagoing ones with shark-like tail fins would be good candidates for that condition; still, good to have confirmation.

Also, that leaves pretty much the thalattosuchian crocodiles (such as Metriorhynchus) as the sole mesozoic sea reptiles with an unknown reproductive method.

I always expected marine reptiles to give live birth. Nothing surprising there at all.

Well, turtles ARE marine reptiles, or at least ancestrally aquatic (tortoises seem to descend from aquatic turtles, and the Triassic proto-turtles such as Odontochelys support that), yet they still come to shore to lay eggs.

Then again, turtles are quite puzzling in their phylogenic postion, but they are looking like archosauromorphs, in contrast to the others, which are commonly recovered as lepidosauromorphs and therefore closer to lizards.

Seeing how other archosauromorphs tend to remain as oviparous despite being adapted to a marine life (crocs lay eggs, incluiding those belonging to pelagic groups such as the gharial (this one is secondarily a freshwater dweller), and even penguins still lay eggs), there may be some limitation that prevents the evolution of viviparity in this group. This can be easily disproven by discovering a viviparous archosauromorph, but we don't have a potential mechanism to understand what is going on.

I meant the ones that obviously couldn't crawl onto land.

You'd be surprised at how adamant certain sectors of the internet can be about the possibibility of Elasmosaurus being able to go into land...

Chimpanzees show ability to plan route in computer mazes: "Chimpanzees are capable of some degree of planning for the future, in a manner similar to human children, while some species of monkeys struggle with this task, according to researchers."

Strange rituals or cannibalism? Neanderthals manipulated bodies of adults and children shortly after death: "Neanderthals from the French region of Poitou-Charentes cut, beat and fractured the bones of their recently deceased companions, as revealed by the fossil remains of two adults and a child found at the Marillac site. These manipulations have been observed at other Neanderthal sites, but scientists still do not know whether they did this for food or ceremony. Scientists have discovered a large quantity of bone remains of these hominids."

How sea snails learned to gobble fish: "Fish-hunting sea snails need a few good tricks if they want a meal. For instance, some species of venomous cone snails do their angling with a potent toxin that wreaks havoc on a fish’s nervous system. But scientists didn’t know the origin of this surprising adaptation, which allows the sluggish mollusks to catch much faster prey. Now, new research in the Proceedings of the National Academy of Sciences has unraveled this evolutionary mystery by uncovering a 'smoking gun' signature present in the venom of fish-eating snails and their worm-loving cousins."

New whale species identified?: "A new species of whale may be cruising the icy cold waters of the Antarctic.

Scientists have recorded a unique whale song, which they can’t identify, in the area.

Evidence for the species is tantalising, rather than strong, as the song could be from one of a few known species of beaked whale.

But it has a structure that doesn’t quite fit any known beaked whales; leaving open the possibility it is from a new species."

Bone eating worms dined on marine reptile carcasses: "A species of bone-eating worm that was believed to have evolved in conjunction with whales has been dated back to prehistoric times when it fed on the carcasses of giant marine reptiles."

40 million-year-old family tree of baleen whales: "New research is providing the most comprehensive picture of the evolutionary history of baleen whales, which are not only the largest animals ever to live on earth, but also among the most unusual."

But regarding their theories, why did the sperm whale manage to stick around?

World’s oldest stone tools discovered in Kenya: "Researchers at a meeting here say they have found the oldest tools made by human ancestors—stone flakes dated to 3.3 million years ago. That’s 700,000 years older than the oldest-known tools to date, suggesting that our ancestors were crafting tools several hundred thousand years before our genus Homo arrived on the scene. If correct, the new evidence could confirm disputed claims for very early tool use, and it suggests that ancient australopithecines like the famed 'Lucy' may have fashioned stone tools, too."

Well, if chimps can use tools, I don't see why australopithecines couldn't too.

Paleoanthropologists tend to think of human evolution as a lineal process, so, a typical branching cladogram, with several lineages coexisting, tends to feel alien to the field (in other words, "Homo habilis evolved from Australopithecus, how can later be found in the same rocks as the former?". And that view being quite common across that field tends to end up making sensationalist headlines which are not that odd, compared to your average mammalian lineage subject to plio-pleistocene diversification. A damn shame, but hopefully the field will keep evolving into something less dogmatic and not conflicting with general zoology.

And, about whales, sperm whales were, IIRC, closer to dolphins than to baleen whales (still, one of the earliest outgroups of odontocetes). Add to that that the pigmy and dwarf sperm whales are still living species, and one can come to the conclussion that gigantism happened numerous times within cetaceans, and secondary dwarfism probably too, as well.

I guess the point I'm trying to make is why didn't sperm whales go extinct like the toothed "baleen" whales, since if that theory's correct the same pressures would've wiped them out too.