Under the bright sunlight, tiny, green creatures move gracefully in their pond of water. With two long antennae' leading the way, these creatures seem to be swimming about randomly, looking as if they are trying to position themselves in the right place to receive signals from outer space. Despite their appearances, these small creatures are not the classical science-fiction inhabitants of Mars, or "E.T." lost on Earth. They have lived on Earth for millions of years. They are Chlamydomonas.

Many diseases, such as Huntington's disease and most cancers, occur through the expression of mutant genes, causing the formation of proteins whose actions harm the host. If the formation of these proteins could somehow be stopped, the diseases they cause would most likely cease to exist.

Hagfish are among the many curious organisms living in the deep oceanic benthos. At first glance, the hagfish's dark, quiet environment appears extremely stable and unchanging - even quite dull. It's not always so still, though. Scavenging brittle stars may stampede over the soft silt mounds created by creatures that live within the sediments, destroying the mound and possibly trapping the inhabitant beneath the mix of silt and mud. "Benthic storms" of sudden water flow can occur from either falling objects or large marine fauna. Sinking human vessels or gigantic food falls such as whale carcasses can cause large disturbances.

Producing energy with water as the only by-product is the attractive concept behind fuel cells. They function by combining hydrogen with oxygen - a simple reaction. Oxygen occurs in air, but highly-reactive hydrogen does not exist naturally in isolation. Current fuel cell research focuses on finding appropriate hydrogen sources and methods for accomplishing this reaction.

By the late 1980s and early 1990s, the evidence supporting the Impact Theory was almost overwhelming. Many geologists and paleontologists began to wonder, "If it could happen once, could it happen twice?"

Here, in the second part of our series, we explore some very recent research that suggests a meteorite may have been the culprit not only in the K-T mass extinction, but also in some of the most devastating biological crises in the history of the earth.