Wild Things: Tarantulas, Jellyfish and More…

Mother bears have a fierce reputation, but they’re not the ones to worry about. Researchers led by the University of Calgary analyzed 59 fatal black bear attacks in the United States and Canada between 1900 and 2009. Most incidents could be blamed on hungry males. The bears most often attacked people traveling alone or in pairs, predominantly in August when black bears bulk up before denning.

Hummingbirds captured on high-speed video surprised University of Connecticut scientists with the way they drink; a bird dips its tongue in nectar, widens the forked tip and unfurls a fringe of hairlike structures. When the tongue leaves the nectar, the tip contracts and the fringe rolls back, trapping nectar. The study refutes the long-held assumption that hummingbirds rely on capillary action to draw nectar up through grooves in their tongues.

Name: Paranthropus boisei, a human relative that lived in East Africa from about 2.3 million to 1.2 million years ago.
Dentition: Its massive jaw and flat molars gave rise to the belief that its diet consisted of nuts, which other nearby primates ate also. Its nickname is “Nutcracker Man.”
Nutrition: A new analysis of carbon isotopes in teeth from 22 individuals strongly suggests that P. boisei ate grasses and sedges instead.
Competition: “It was not competing for food with most other primates,” says Kevin Uno of the University of Utah, a researcher on the new study, “but with grazers”—ancestors of today’s zebras, pigs and hippos.

Researchers studying the box jellyfish Tripedalia cystophora in Puerto Rico observed that four of the species’ 24 eyes always point up. The translucent eyes, inside the jellyfish’s body, seem specialized for peering beyond the water surface to detect tree branches, which direct the jellies to the mangrove swamps where they feed.

All spiders secrete silk from their abdomens, but it now appears that tarantulas can also shoot silk from their feet. Researchers in Britain turned tarantula glass tanks sideways, shook them and found nearly invisible silk threads that slipping spiders had deployed to hang on.