Ecology
Are synthetic chemicals altering the fabric of our bodies?
It’s certainly worth reflecting on: It’s fair to say that PCBs and fluorocarbons have altered the biochemical composition of the food web and the interior of the human body, and in the case of the PFASs, the water we drink. (Some PFASs can even fall with rain.) These have been swift, sweeping changes over the course of just three or four generations, too quick for the slow-grinding machinery of human evolution to adapt. And yet, PCBs and PFASs are now an integral part of the human story. They pass from species to species, from mother to child. They are present from conception to death, and consumed with daily meals and holy feasts. The presence of PCBs alone shapes how humankind Read More ›
Can beavers contribute to evolution by transforming the tundra?
Anyone familiar with beavers will know that the big busy rodents can transform roads into ponds. They are making a comeback in Alaska: Beavers may be infiltrating the region for the first time in recent history as climate change makes conditions more hospitable, says Ken Tape, an ecologist at the University of Alaska Fairbanks. Or maybe the expansion is a rebound after trapping reduced beaver numbers to imperceptible levels in the early 1900s, he says. Nobody knows for sure. And the full range of changes the rodents are generating in their new Arctic ecosystems hasn’t been studied in detail. But from what Tape and a few other researchers can tell so far, the effects could be profound, and most of Read More ›
Researcher: Human impact is a “reshaping of the tree of life”
Sarah Otto, a University of British Columbia researcher, tells media about her research, Her paper is replete with examples from bird species slowly forgetting to migrate to mosquito breeds adapted specifically to underground subway tunnels. Backyard bird feeders are behind changes in the beak shape and strength of house finches. Different mammals are becoming nocturnal as a way to avoid human conflict. Introduced species change the ground rules for native plants and animals. It’s a mistake to think evolution requires millennia, said Otto. “Evolution happens really fast if the selection regimes are strong. We can see sometimes in plant populations evolutionary change in the course of years.”Bob Weber, “Humans are having huge influence on evolution of species, study says” at CBC Read More ›
News: Anthropologist does not see chimpanzees as fuzzy humans
It’s great to see concern for primate apes taking a rational turn that can actually be in their interests: In recent years, wildlife sanctuaries, conservation organizations, and animal rights groups have told the public to stop touching chimpanzees and other wild animals. National Geographic, PETA, and even Instagram draw explicit links between human touch and harm. They discourage wildlife enthusiasts from visiting “fake sanctuaries” that let tourists play with wild animals. Sanctuary accreditation organizations, such as the Pan African Sanctuary Alliance (PASA), can refuse to accredit facilities that allow visitors to touch primates. They say that visitor illness, easily communicated through touch, can kill a young chimpanzee. Moreover, this touch—even if it is playful—can harm chimps and other wild animals Read More ›
Assumed extinct, tree kangaroo reappears
The wondiwoi was spotted by an expedition led by amateur botanist Michael White, who spends vacations looking for rare flora: The Wondiwoi tree kangaroo had not been collected, seen, or reported since that first sighting [in 1928]. Despite weighing up to 35 pounds, tree kangaroos are remarkably cryptic, often remaining totally hidden high in the forest canopy. On one of the final days of their expedition, having had no luck spotting one, the crew started to head down. That was when the hunter “spotted a kangaroo 30 meters [90 feet] up,” Smith says. “After a lot of scrambling around trying to get my lens to focus on the animal peeking out from behind the leaves, I got a few half-decent Read More ›
New Scientist: Monkeys “look like” they are domesticating wolves
Then that is the monkeys’ mistake, not the wolves’: In the alpine grasslands of eastern Africa, Ethiopian wolves and gelada monkeys are giving peace a chance. The geladas – a type of baboon – tolerate wolves wandering right through the middle of their herds, while the wolves ignore potential meals of baby geladas in favour of rodents, which they can catch more easily when the monkeys are present. The unusual pact echoes the way dogs began to be domesticated by humans and was spotted by primatologist Vivek Venkataraman, at Dartmouth College in New Hampshire, during fieldwork at Guassa plateau in the highlands of north-central Ethiopia. We do not in fact know how humans first domesticated wolves. Dogs were domesticated between Read More ›
Researchers: As soon as macroscopic life evolved, it formed communities
Plants use flashes of fluorescent light to warn leaves against insects
From ScienceDaily: In one video, you can see a hungry caterpillar, first working around a leaf’s edges, approaching the base of the leaf and, with one last bite, severing it from the rest of the plant. Within seconds, a blaze of fluorescent light washes over the other leaves, a signal that they should prepare for future attacks by the caterpillar or its kin. That fluorescent light tracks calcium as it zips across the plant’s tissues, providing an electrical and chemical signal of a threat. In more than a dozen videos like this, University of Wisconsin-Madison Professor of Botany Simon Gilroy and his lab reveal how glutamate — an abundant neurotransmitter in animals — activates this wave of calcium when the Read More ›
Humans lived in Madagascar 6000 years earlier than thought
And probably did not kill off all the elephant birds, as often claimed, say researchers: Analysis of bones, from what was once the world’s largest bird, has revealed that humans arrived on the tropical island of Madagascar more than 6,000 years earlier than previously thought—according to a study published today, 12 September 2018, in the journal Science Advances. A team of scientists led by international conservation charity ZSL (Zoological Society of London) discovered that ancient bones from the extinct Madagascan elephant birds (Aepyornis and Mullerornis) show cut marks and depression fractures consistent with hunting and butchery by prehistoric humans. Using radiocarbon dating techniques, the team were then able to determine when these giant birds had been killed, reassessing when humans first Read More ›
Contra stereotype, some sharks eat seagrass
Just when we thought we had these thing figured out. Intro of topic Sharks are infamous meat-eaters. The ocean’s buffet of fish, crabs, mussels, shrimp and krill fill the legendary predators’ stomachs and give them sustenance. Now researchers have discovered that one particular species, bonnethead sharks, also dine on seagrass to meet their nutritional needs. The discovery means bonnethead sharks are not carnivores but omnivores — a distinction that changes how the coastal swimmers influence the fragile ecosystems they call home. … That means these coastal sharks once thought to be solely meat-eaters are actually omnivorous and the only known shark species to eat plants. That distinction changes things for ecosystem managers since omnivorous fish are food web stabilizers. Roni Read More ›
Another academic freedom meltdown in science, this time re GMOs
From Alex Berezow at American Council on Science and Health: Pro-GMO Professor Fired for Endorsing Glyphosate David Zaruk is an expert in European Union regulations and risk communication. He writes a blog, titled The Risk-Monger, which largely examines regulatory issues involving biotechnology, such as GMOs and glyphosate. For nearly a decade, he also was an adjunct professor of communications at Université Saint-Louis in Brussels, Belgium. As Dr. Zaruk writes in a lengthy blog post, he recently lost his job from the university. Why? According to Dr. Zaruk, it’s because he is avidly pro-biotechnology and another professor (at a different university!) didn’t like it. So, he pulled a few strings and got Dr. Zaruk fired. It should be noted that Olivier Read More ›
Butterfly “extinction” that wasn’t
From ScienceDaily: The evolution of wild species, adapting them to human management practices, can cause localised extinctions when those practices rapidly change. And in a new study published in Nature, Professors Michael C. Singer and Camille Parmesan have used more than 30 years of research to fully document an example of this process. A large, isolated population of a North American butterfly evolved complete dependence on an introduced European weed to the point where the continued existence of the butterfly depended on the plant’s availability. The insects then became locally extinct when humans effectively eliminated that availability, confirming a prediction made by the same authors in a 1993 Nature paper. Thus the advent of cattle ranching more than 100 years Read More ›
Biogeography: Life before ecology, when Canadian beavers overran Tierra del Fuego
A long time ago, everyone thought that nature was just a big, easily tinkered machine, there was a fad for transporting awesomely successful life forms across the globe (which they would not usually do themselves*). From Daniel Martins at the Weather Network: If you’re wondering what in blazes Canadian beavers are doing so far away from the Frozen North, that is a excellent question whose implications the Argentine government should probably have thought a little harder about. Instead, it seems to have been with a mixture of pride and hopefulness that, in 1946, the government flew 20 beavers from Manitoba first to Rio de Janeiro, then to Buenos Aires, and then on by seaplane to Lake Fagnano, in the interior of Read More ›
Urban fish differ from rural fish but is that really “evolution”?
From Brian Langerhans and Mick Kulikowski at NC State University: A North Carolina State University study examining the effects of urbanization on the evolution of fish body shape produced both expected and surprising results: One fish species became more sleek in response to urbanization, while another species became deeper bodied in urban areas. Generally, urbanization produces conditions that make water in streams flow more variably and more quickly during rain storms. So NC State biologists hypothesized that fish would quickly evolve a body shape that improves swimming efficiency in response to changes in stream water velocity caused by urbanization. “We wanted to test rapid body shape evolution in western and central North Carolina stream fish in response to urbanization,” said Read More ›