Decades of wild swings in crab populations – some natural, some human-caused – dramatize the myriad issues surrounding questions about sustainable fisheries and the ecosystems that support them.
Natural selection has played a role in the development of the many skins patterns of the tiny Ranitomeya imitator poison dart frog, according to a study that will be published in an upcoming edition of American Naturalist by University of Montreal biologist Mathieu Chouteau. The researcher’s methodology was rather unusual: on three occasions over three days, at two different sites, Chouteau investigated the number of attacks that had been made on fake frogs, by counting how many times that had been pecked. Those that were attacked the least looked like local frogs, while those that came from another area had obviously been targeted. (more…)
*3.2 million-year-old human predecessor had arches in feet*
COLUMBIA, Mo. – Feet arches give humans a spring in their steps, shock absorbing abilities, and stiff platforms to propel themselves forward, allowing them to walk upright consistently. Now, researchers at the University of Missouri and Arizona State University have found proof that arches existed in a predecessor to the human species that lived more than 3 million years ago. This discovery could change scientists’ views of human evolution. The study is being published this week in Science.
Carol Ward, an MU researcher in the Department of Pathology and Anatomical Sciences at the MU School of Medicine, and William Kimbel and Donald Johanson, director and founding director of the Institute of Human Origins at Arizona State University, studied a 3.2 million-year-old fourth metatarsal of Australopithecus afarensis. A team from the Institute of Human Origins and National Museum of Ethiopia led by Kimbel discovered the fossil in Hadar, Ethiopia. The species is often referred to as “Lucy,” the nickname of the most complete fossil skeleton of the species to be discovered. (more…)
Research by the University of Exeter has revealed that ants have a big impact on their local environment as a result of their activity as ‘ecosystem engineers’ and predators.
The study, published in the Journal of Animal Ecology, found that ants have two distinct effects on their local environment. (more…)
The fears connected with shark attacks are stronger in the world today than those related to much more dangerous predators – crocodiles. However, crocodiles pose a greater threat to humans than sharks do.
A crocodile snatched Hendrik Coetzee, a South African guide, 35, from his kayak while he led an American expedition into the heart of Congo last week. Two American tourists could only watch the scene in horror as the guide was killed and eaten by the predator. They paddled to safety unharmed. Coetzee’s body has not been recovered.
Stories about croc attacks are just as terrible as they are hopeless. Experts say that it is possible to stay to fight off a shark, but it is much more difficult or even impossible to rescue themselves from an attacking croc. (more…)
LARAMIE, Wy. — Previous research has claimed that the reintroduction of wolves to Yellowstone National Park in 1995 is helping restore quaking aspen in risky areas where wolves prowl. But apparently elk hungry for winter food had a different idea.