This scanning electron microscope image of the tarsal claw of the horsefly Tabanus sulcifrons juxtaposes the complexity and simplicity of “nature’s Velcro.” The menacing sturdiness of the tarsal claws contrasts with the delicate nature of the tarsal pad, with fine, hooked hairs that allow the fly to hold on to animal fur.
Image credit: Valerie A. Tornini, Duke University
Jan. 24, 2013 — An insect with a tiny brain and minimal computing power has become the first animal proven to use the Milky Way for orientation. Scientists from South Africa and Sweden have published findings showing the link between dung beetles and the spray of stars which comprises our galaxy.
Although their eyes are too weak to distinguish individual constellations, dung beetles use the gradient of light to dark provided by the Milky Way to ensure they keep rolling their balls in a straight line and don’t circle back to competitors at the dung pile.
“The dung beetles don’t care which direction they’re going in; they just need to get away from the bun fight at the poo pile,” said Professor Marcus Byrne from Wits University.
The image above shows a California sea hare (Aplysia californica), a type of sea slug, inking. Looking a little like a rabbit, sea hares are a common treasure in Santa Barbara’s Coal Oil Point tidepools. They can get up to 16 pounds but are usually more like three to four pounds in the lower pools. Although these slugs appear to be just a big blob, they have a hidden trick — beautiful purple ink that can be released from a gland in their mantle cavity if you reach inside the skin flaps on the top and tickle them. In nature, this acts as a smoke screen (similar to an octopus’ ink). California sea hares are herbivorous, with a diet consisting primarily of red and brown seaweed, which gives the animal its typically dark coloration.
This is not a spider. Nor is it a spit wad target or a child’s miscalculated attempt at a paper mâché skeleton. This spider-shaped mass is actually a clever decoy. The inch-long assemblage of leaves, twigs, and dead bugs was meticulously arranged by a spider less than a quarter its size. The arachnid artist created this body double on his web in the Peruvian Amazon, and lurks on the strands above it, pulling strings to make the puppet move.
Biologist Phil Torres recently discovered the spider and suggests in a blog entry that its behavior is an elaborate defense mechanism that encourages predators to attack the bigger, flashier spider rather than its sneaky creator.
Such strategic distractions are characteristic of spiders in the genus Cyclosa, butother species build blob-shaped constructions which lack legs altogether. And the decoys certainly don’t move. Scientists are thus suggesting that this spider is a new Cyclosa species. Definitive identification studies are on hold until January when researchers can get a permit to actually collect the spiders and take a closer look.
You won’t findSpirobranchus giganteus, also known as the Christmas tree worm, eating your fir tree this year. The common name for these worms is derived from their appearance, not their habitat or diet. Each worm has two brightly colored crowns that protrude from its tube-like body. These Christmas tree-like crowns are composed of radioles, or hair-like appendages radiating from the worm’s central spine. These appendages are used for respiration and to catch dinner, which typically consists of microscopic plants, or phytoplankton, floating in the water. These worms are sedentary, meaning that once they find a place they like, they don’t move much. In fact, while the colorful crowns of these worms are visible, most of their bodies are anchored in burrows that they bore into live coral. When startled, Christmas tree worms rapidly retract into their burrows, hiding from would-be predators.
Young sibling polyps of staghorn coral (Acropora millepora) three days after settlement. In a National Science Foundation-supported study, researchers found that the ability to fluoresce may influence whether or not the coral settle on the reef of their origin, or disperse and go elsewhere.
Staghorn coral (Acropora millepora) were the focus of a National Science Foundation (NSF)-supported study by Misha Matz, an assistant professor of integrative biology at the University of Texas at Austin, and colleagues, to address coral reef connectivity, genetics of physiology and life history traits, and their evolutionary modifications in response to ongoing climate change.
Results of the study found that young staghorn coral that fluoresce redder are less likely to settle and develop into coral polyps than their greener peers, a finding that may help scientists monitor how corals adapt to global warming because the less likely coral larvae are to settle, the more likely they will disperse from their reef of origin.
Stittsville, Ontario, Canada
Chrysolina fastuosa (Micro leaf beetle) on a pin head (40x)