Sharks "on the brink"

Sharks are on the brink of extinction, the alarm is sounded, as nine more species of sharks are added to the IUCN's Red List of endangered species. According to the article, contributing factors are the long times that sharks take to reach maturity, and the common perception that since sharks are widely-ranging, fishing intensively in one spot should not affect the whole population. However, fisheries around the world are intensive enough to affect worldwide populations. Scientists are also only just beginning to figure out the patterns of shark migrations for most of the species that we know of. The article also relates how decimation of shark populations in the Northern Atlantic released a species of ray, the cownose ray, from predation, which in turn fed on and reduced the numbers of bay scallops around North Carolina.

Birds not bird-brained

How do starlings flock? Instead of just focusing their attention on the bird immediately in front, they actually pay attention to up to seven other individuals in the flock and respond to their movements.

World's weirdest amphibians!

As advertised:

World's weirdest amphibians

Who else thinks the giant salamander is creepy?

Ants, Acacia trees, and herbivores

It's well known that acacia trees produce food bodies and offer nesting sites for ants, which help it to defend against herbivores that feed on the tree's leaves. But what happens when the herbivores are removed? The trees paradoxically grow sicker and lose leaves. Apparently when herbivores are not browsing on the leaves, the trees reduce their investment in providing resources to the ants, and the ants start to leave the trees. This allows the establishment of wood-boring beetles which bore tunnels into the wood of the trees, causing them to weaken. Amazing! It's like playing Jenga.

Monarch Butterfly Circadian Rhythms

New research has shown that the monarch butterfly uses a light-sensitive cryptochrome protein to regulate its internal circadian rhythm, and this protein is also linked to its navigational ability, suggesting that "part of the remarkable navigational ability of the butterfly relies on its ability to integrate temporal information from the clock with spatial information from its visual system. This allows the monarch to correct its course as light shifts across the sky over the course of the day."