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There's No Scent Like Home: New Research Shows Larval Fish Use Smell To Return To Coral Reefs:

Tiny larval fish living among Australia's Great Barrier Reef spend the early days of their lives swept up in ocean currents that disperse them far from their places of birth. Given such a life history, one might assume that fish populations would be genetically homogeneous within the dispersal area. Yet the diversity of reef fish species is high and individual reefs contain different fish populations. For such rich biodiversity to have evolved, some form of population isolation is required. New research from MBL (Marine Biological Laboratory) Associate Scientist Gabriele Gerlach, MBL Adjunct Senior Scientist Jelle Atema, and their colleagues shows that some fish larvae can discriminate odors in ocean currents and use scent to return to the reefs where they were born. The olfactory imprinting of natal reefs sheds light on how such a wide diversity of species arose. The homing behavior of reef fishes, the researchers contend, could support population isolation and genetic divergence that may ultimately lead to the formation of new species.

World's Largest Flower Evolved From Family Of Much Tinier Blooms:

The plant with the world's largest flower -- typically a full meter across, with a bud the size of a basketball -- evolved from a family of plants whose blossoms are nearly all tiny, botanists write this week in the journal Science. Their genetic analysis of rafflesia reveals that it is closely related to a family that includes poinsettias, the trees that produce natural rubber, castor oil plants, and the tropical root crop cassava. [---] "For nearly 200 years rafflesia's lineage has confounded plant scientists," says Davis, an assistant professor of organismic and evolutionary biology in Harvard's Faculty of Arts and Sciences. "As a parasite living inside the tissue of a tropical vine, the plant lacks leaves, shoots, or roots, making it difficult to compare to more conventional plants. Most efforts to place plants in the botanical tree of life in the past 25 years have tracked ancestry using molecular markers in genes governing photosynthesis. Rafflesia is a non-photosynthetic parasite, and those genes have apparently been abandoned, meaning that to determine its lineage we had to look at other parts of the plant's genome."

Prenatal Cocaine's Lasting Cellular Effects:

Although the "crack baby" hysteria of the 1980s was greatly exaggerated, cocaine use during pregnancy can cause subtle but disabling cognitive impairments -- attention deficits, learning disabilities and emotional problems. A recent study by investigators at the Vanderbilt Kennedy Center for Research on Human Development may help explain the long-term behavioral and neurological problems associated with prenatal exposure to cocaine. In a recent issue of the Journal of Neuroscience, Gregg Stanwood, Ph.D., and Pat Levitt, Ph.D., report that prenatal cocaine exposure in rabbits causes a long lasting displacement of dopamine receptors in certain brain cells, which alters their ability to function normally.

Musician In The Mirror: New Study Shows Brain Rapidly Forms Link Between Sounds And Actions That Produce Them:

A new imaging study shows that when we learn a new action with associated sounds, the brain quickly makes links between regions responsible for performing the action and those associated with the sound.