The researchers suggest this precise spatial control of amino acids on inorganic surfaces could have many technological applications.

Tracing the Rise of Ants

In a perspective article, Edward O. Wilson and Bert Hlldobler explore the evolutionary history of ants, tracing their waves of expansion from the first appearance more than 100 million years ago.

Over the past two decades, fossil discoveries combined with studies of anatomy, behavior, and DNA have helped clarify the phylogeny of ants, the authors say. Yet some puzzles remain, such as how the important and ancient subfamily Ponerinae spread so widely while retaining relatively primitive social organization--a question the authors term "the ponerine paradox."

A full explanation will require further discoveries in paleontology and ecology, the authors note. Until then, Wilson and Hlldobler offer a combined phylogenetic and ecological "dynastic-succession" hypothesis that ties together existing knowledge.

Key events in this history include an initial adaptation to forest ground litter and soil coincident with a surge in flowering plants, then an advance to ecological dominance in tropical forests, and finally a broad expansion up into trees and outward into drier environments.

Fish Genitalia May Balance Attractiveness with Predatory Escape

Male genital size in some fish species may be driven by competing evolutionary mechanisms, reflecting a tradeoff between the capacity to attract mates and the ability to quickly evade predators, researchers report.

Diversity of male genitalia size in animals with internal fertilization has intrigued scientists. Most evolutionary explanations have centered on postmating sexual selection,
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Contact: Leikny Johnson
PNASNews@nas.edu
202-334-1310
Proceedings of the National Academy of Sciences (PNAS)
16-May-2005