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Evolution

  • North America alone is home to hundreds of migratory bird species. Ever see a songbird and wonder where they’ve been or where they’re going next? Now you can! Audubon’s bird migration web app is powered by research from hundreds of partners, including Cornell. Cornell in particular has an eBird database maintained by their Lab of Ornithology. It’s a remarkable high-quality database. Some of the other data sources:

    Marshall Johnson, chief conservation officer for the National Audubon Society shared some thoughts on the importance of publishing such a tool. We have a responsibility to understand and conserve these environments:

    “The most effective migratory bird conservation efforts are informed by the best-available science, engage local communities, and are supported by partners and governments across their migratory ranges,” […] “The Bird Migration Explorer makes it plain to see how connected we are by these incredible birds. It’s clearer than ever that we have a collective responsibility and opportunity across the hemisphere to protect these birds and the places they need, today and tomorrow.”

    Who would have known that the Peregrine Falcon migrated so far south!

  • A century has passed since the legendary skull fragment was unearthed. Recently, archaeologists confirmed our youngest ancestor. The bones Unearthed back in 1931 have been confirmed to be the youngest Homo erectus remains ever found. It could be the last tangible (or measurable) youngest connection to our human ancestors. These remains aren’t to be confused with Java Man, which was also unearthed on the Indonesian island of Java (Java Man was excavated back in 1892).

    It’s a remarkable confirmation considering it almost didn’t even happen. Isaac Schultz at Atlas Obscura reports:

    “When you think about it, out of the 25,000 some fossils on the site, only 14 were a Homo erectus,” says Russel Ciochon, a paleoanthropologist at the University of Iowa in Iowa City and lead author of the study, published recently in the journal Nature. “They lucked out. Had they not found the skull, they may not have put such time into it.”

    A skull fragment of H. erectus found nearly a century ago in Java. Source: Macquarie University
  • Kristin Houser writes at The Byte:

    Efforts to control urban rat populations rarely — if ever — result in the complete eradication of the pests. Most of the time, the goal is to simply reduce rodent numbers enough to minimize the spread of disease or damage to property.

    But according to Jonathan Richardson, an assistant professor of biology at the University of Richmond, letting some rats slip through the cracks can cause a local population to swiftly evolve, leading to either of two long-term outcomes: sickly rats or “super” ones.

    Rats are being artificially extinguished at a rate that catalyzes the evolutionary process known as natural selection. In large cities, such as NYC, or Brazil, pesky rodent populations are frequently targeted for extermination with warfarin. A an extremely deadly and potent poison which essentially causes liver failure in mammals. The chemical is so deadly, and so toxic in fact, it has been used to the target feral hog problem in parts of Texas (despite the lack of an EPA approval). Which is extraordinarily dangerous, because warfarin can bioaccumulate and kill grazing livestock and cattle, and could ultimately end up in your food.

    As the breeding pairs of genetically diverse rats dwindles in these urban cities to a smaller and smaller pool, one of two scenarios will unfold for the rat populations:

    Urban rat populations could become extremely weak, diseased and in-bred. In this scenario, it could lead to a total eradication of rats.

    However, in an alternate scenario, it could lead to a super-fit rat population. Whose who survive extermination, pass on those survival traits to offspring and become super rats.

  • Looks like Stanley Miller and Harold Urey were onto something with their experiments back in 1952. Their classic abiogenesis research continues to be refined in a new experiment spearheaded by Thomas Carrell. From Nature:

    Carell, an organic chemist, and his collaborators have now demonstrated a chemical pathway that — in principle — could have made A, U, C and G (adenine, uracil, cytosine and guanine, respectively) from basic ingredients such as water and nitrogen under conditions that would have been plausible on the early Earth. The reactions produce so much of these nucleobases that, millennium after millennium, they could have accumulated in thick crusts, Carell says. His team describes the results in Science on 3 October1.

    The results add credence to the ‘RNA world’ hypothesis, says Carell, who is at the Ludwig Maximilian University of Munich in Germany. This idea suggests that life arose from self-replicating, RNA-based genes — and that only later did organisms develop the ability to store genetic information in the molecule’s close relative, DNA. The chemistry is also a “strong indication” that the appearance of RNA-based life was not an exceedingly lucky event, but one that is likely to happen on many other planets, he adds.

    The results, are essential to the Hot Spring Hypothesis and the origin of complex life on Earth. Pretty awesome!