EAST LANSING, Mich. — Innovative problem solving requires trying many different solutions. That’s true for humans, and now Michigan State University researchers show that it’s true for hyenas, too. (more…)
Robotic boats track radio-tagged common carp in area lakes
As a stiff breeze sweeps across Staring Lake in suburban Minneapolis, a five-foot, antenna-sporting robotic boat plies the water in a back-and-forth pattern.
On the shore, Volkan Isler follows the action as two graduate research assistants launch a second boat.
Today Isler, an associate professor of computer science at the University of Minnesota, and graduate students Pratap Tokekar and Josh Vander Hook have come to the lake to test the newer of the boats. Their mission: developing a new technology to track invasive fish. (more…)
The most common lineages of fish found today in oceans, lakes, and rivers evolved about the same time as mammals and birds, a new Yale University-led study shows.
The comparative genetic analysis of more than 200 fish species, reported the week of Aug. 6 in the Proceedings of the National Academy of Sciences, gave an earlier than expected evolutionary birthday to well-known teleost — or ray-finned — fish such as salmon, bass, or tuna.
The analysis also shows that the very earliest lineages of living teleost fish were eels and bonefishes, not tropical freshwater bonytongue fish as some scientists had proposed. (more…)
ANN ARBOR, Mich.— Predatory beetles can detect the unique alarm signal released by ants that are under attack by parasitic flies, and the beetles use those overheard conversations to guide their search for safe egg-laying sites on coffee bushes.
Azteca instabilis ants patrol coffee bushes and emit chemical alarm signals when they’re under attack by phorid flies. In an article published online July 27 in the journal Ecology and Evolution, University of Michigan researchers and their colleagues show that pregnant lady beetles intercept the ants’ alarm pheromones, which let the beetles know that it’s safe to deposit their eggs. (more…)
Shenandoah National Park, Va. – American eels are declining across their range but are showing indications of a population revival following the removal of a large dam in Virginia.
The removal of Embrey Dam on the Rappahannock River increased American eel numbers in headwater streams nearly 100 miles away, according to research just published by U.S. Geological Survey, U.S. Fish and Wildlife Service, and National Park Service researchers.
American eels undergo long-distance migrations from their ocean spawning grounds in the Sargasso Sea to freshwater streams along the Atlantic coast from northern South America to Greenland. Dams may slow or even stop upstream eel migrations. However, prior to this research, little was known about American eel responses to dam removal. (more…)
When a University of Washington researcher listened to the audio picked up by a recording device that spent a year in the icy waters off the east coast of Greenland, she was stunned at what she heard: whales singing a remarkable variety of songs nearly constantly for five wintertime months.
Kate Stafford, an oceanographer with UW’s Applied Physics Lab, set out to find if any endangered bowhead whales passed through the Fram Strait, an inhospitable, ice-covered stretch of sea between Greenland and the northern islands of Norway. Only around 40 sightings of bowhead whales, which were hunted almost to extinction, have been reported there since the 1970s. (more…)
The number of basking sharks recorded in Britain’s seas could be increasing, decades after being protected from commercial hunting in the late 20th century.
The most comprehensive analysis ever undertaken of basking shark sightings in UK waters, by the University of Exeter, the Marine Conservation Society (MCS), Cornwall Wildlife Trust (CWT) and Wave Action, is published in the journal Marine Ecology Progress Series.
The northeast Atlantic hosted an extensive commercial fishery for basking sharks, mainly in Norway, Ireland and Scotland, where more than 81,000 were killed between 1952 and 2004, hunted largely for their liver oil. Large-scale hunting ended in the UK in the middle of the twentieth century, though it continued at low levels in Norway until 2000. (more…)
Researchers at Yale have identified an ancient slithering creature from the time of T. rex as the most primitive known snake, a finding with implications for the debate over snake origins.
“It’s the missing-link snake,” said Nicholas Longrich, a postdoctoral fellow in Yale’s Department of Geology & Geophysics and the lead author of a paper about the lizard-like snake published July 25 online in the journal Nature. “It’s the ‘Lucy’ of snakes.”
The paper argues that snakes descend from terrestrial rather than marine ancestors, as recently proposed by others, and that snakes emerged once lizards developed long, limbless bodies for burrowing. (more…)
