Parasitic wasps propagate by injecting their eggs into a caterpillar that then becomes paralyzed as the eggs inside develop into wasp larvae. The wasp larvae kill the caterpillar host as they feed on it, form cocoons, and finally develop into wasps. In attempting to discover how such wasps detect the presence of the caterpillar hosts that are so critical to the wasps ' propagation, researchers have uncovered an intriguing defense mechanism developed by the plants on which the caterpillars feed.

When chewed on, many plants release volatile compounds from both damaged and undamaged tissues. When these compounds are toxic to the insects that feed on the plants, they can help defend the plants from such attacks. However, the plants on which the wasps ' caterpillar hosts feed have evolved an even more complex defense: the caterpillar-infested plants appear to release volatile chemicals that attract parasitic wasps, which then prey on the caterpillars. Scientists originally suspected that the wasps were attracted by an odor, reminiscent of cut grass, that is released as the caterpillar feeds, but a recent study suggests that a different set of volatile attractants is involved. In this study, when researchers used a razor blade to mimic caterpillar damage on the leaves, only grassy odors were emitted, not the volatile compounds that attracted wasps. However, when oral secretions from the caterpillars were applied to these damaged leaves, the leaves released the wasp attractants several hours later. Further tests revealed that oral secretions placed on the razor-damaged leaves stimulated the release of such attractants, making the plants as attractive to wasps as plants that had suffered actual caterpillar damage. These results suggest that chemicals from the caterpillar must be present for these attractants to be released and that unlike the grassy scent, which emanates only as the caterpillar on the plant, the wasp attractants are produced several hours after the attack and persist for several hours, perhaps days. Researchers have launched additional studies to determine whether the wasps ' capacity to prey on caterpillars can be enhanced to the extent that the wasps could be used as a natural pesticide to " police " plants and protect them from crop-destroying caterpillars.

Light exists on a spectrum of frequencies extending from gamma rays at the highest frequencies to radio waves at the lowest, though human eyes are sensitive to only a narrow range of frequencies in the middle known as the visible spectrum. The different colors we see correspond to the different frequencies of light within that range. Given that there are so many frequencies of light, one might wonder why our eyes didnt evolve to be sensitive to more frequencies.

Gamma rays from space collide with Earth ' s atmosphere, which converts some of their energy to heat and creates a distinctive cascade of subatomic particles down toward the ground. However, the rays themselves are entirety absorbed before they can reach Earth ' s surface. Thus, Earth would appear to be pitch black to eyes that were only sensitive to gamma rays. Similarly, the majority of frequencies of light that are higher or lower than those in the visible spectrum—such as ultraviolet and most infrared frequencies, respectively—are mostly or entirely absorbed by Earth ' s atmosphere.

One reason we see the frequencies we do is that visible-spectrum light generally passes through our atmosphere without being absorbed or reflected. Another reason is that the Sun, in some respects an average star, emits most of its light at frequencies in the visible spectrum, whereas a hot star emits most of Its light at ultraviolet frequencies and a very cool star emits most of its light at infrared frequencies. Indeed, to remarkably high precision, the human eye to most sensitive to the exact frequency in the yellow part of the spectrum at which the Sun is the brightest

Even if there are living beings on other planets, it is not likely that they would see mainly at very different frequencies than we do. Virtually all gases that are abundant in the cosmos tend to allow frequencies in the visible spectrum to pass through while absorbing other frequencies, and all but the coolest stars put out much, If not most, of their light in the visible spectrum. If there are Irving beings on other planets, they probably see at roughly the same frequencies as we do, though there may be occasional exceptions.

Members of many primate species approach an opponent shortly after conflict and initiate behaviors such as embracing, grooming, or huddling—a phenomenon researchers call postconflict reconciliation. Existing research, however, suffers from several shortcomings. The variability between groups of the same species is rarely addressed; the majority of studies investigate only a small fraction of the pairings that exist in a given group; and almost all reports are restricted to animals in captivity.

In an attempt to address some of these shortcomings, Sommer et al. recentfy conducted a study of postconflict reconciliation in wild Hanuman langurs, a species of colobine monkey. They observed rates of postconflict reconciliation much lower than would be expected based on previous research, and found that over 80 percent of all pairings exhibited no postconflict affinity whatsoever. The rarity of friendly postconflict reunion in wild langurs draws attention to the possibility that conflicts are modulated through avoidance. The option of temporarily avoiding contact with opponents is not easily available to captive primates, and certainly not to the extent present in the wild. Still, studies of postconflict behavior of primates in captivity remain valuable: above all, they demonstrate the flexibility of nonhuman primates in various environments. It is likely, however, that the reported frequency of reconciliation among primates is artificially inflated by the conditions of captivity.

United States Geological Survey scientists have found that a cooling in Pacific

Ocean temperatures led to increases in ecologically threatening phytoplankton

blooms in San Francisco Bay, California. The declining temperatures took place off

the coast of California between 1999 and 2004. The occurrence of these blooms

is surprising because such blooms are normally associated with increases in the

amount of nutrients, such as nitrogen and phosphorus, entering estuaries from

such sources as wastewater treatment plants and agricultural fields. In this case,

the bay’s phytoplankton blooms occurred during a period of decreasing nutrient

concentration and inputs.

The scientists discovered the effects of the cold Pacific temperatures by using

biological and water-quality data collected over twenty-five years. The colder

temperatures caused changes in the types, abundance, and migration patterns of

marine life into the San Francisco Bay from coastal ocean waters. For example,

marine life, such as fish, shrimp, and crabs, migrated to the warmer waters that

are found in the bay.

The migrations increased the numbers of predators such as bay shrimp and

Dungeness crabs that eat filter feeders, such as clams. Clams can filter large

quantities of phytoplankton from the bay’s water, which can prevent

phytoplankton blooms. With the increase in predators, there was a corresponding

decrease in clam populations and an increase in phytoplankton.