Wilderness and biodiversity conservation.

Human pressure threatens many species and ecosystems, so conservation efforts necessarily prioritize saving them. However, conservation should clearly be proactive wherever possible. In this article, we assess the biodiversity conservation value, and specifically the irreplaceability in terms of species endemism, of those of the planet's ecosystems that remain intact. We find that 24 wilderness areas, all > or = 1 million hectares, are > or = 70% intact and have human densities of less than or equal to five people per km2. This wilderness covers 44% of all land but is inhabited by only 3% of people. Given this sparse population, wilderness conservation is cost-effective, especially if ecosystem service value is incorporated. Soberingly, however, most wilderness is not speciose: only 18% of plants and 10% of terrestrial vertebrates are endemic to individual wildernesses, the majority restricted to Amazonia, Congo, New Guinea, the Miombo-Mopane woodlands, and the North American deserts. Global conservation strategy must target these five wildernesses while continuing to prioritize threatened biodiversity hotspots.

Biodiversity hotspots revealed.

PIP: US-based Conservation International has completed an updated version of its Global Biodiversity Hotspots map. This map shows areas of key importance in the battle to save the planet's diversity of life. In this article, an explanation of what the map reveals and how it can be used to develop a global conservation strategy is presented. Focusing on the terrestrial realm, analysis identified regions with 0.5% or more of total global plant diversity represented as endemic species and tropical rainforest hotspots generally having a very high vertebrate diversity and endemism. The first 25 high-priority terrestrial biodiversity hotspots included tropical rainforest areas, tropical dry forest, arid systems, temperate Mediterranean-type ecosystems, savannas, and steppes as well as combinations of these areas. Among these 25 biodiversity spots, top-priority spots have been specified since total diversity in such areas is much higher than what is represented by the endemic alone. Focusing conservation efforts on these areas can achieve maximum impact on the preservation of the Earth's environment.^ieng

Function of the subclavius muscle in a nonhuman primate, the spider monkey (Ateles).

Within the primate order, the morphology of the subclavius muscle is known to be unique among the prehensile-tailed South American monkeys. 3 spider monkeys, Ateles, were monitored electromyographically to determine the recruitment of this muscle during various locomotor and postural activities. Rather than indicating a static stabilizing function, which has typically been inferred from classical anatomical studies, results from this study suggest that the subclavius performs more as a dynamic element in movements of the pectoral girdle during brachiation, vertical climbing, pronograde quadrupedalism and leaping. Complementary activity patterns were also identified between the subclavius and the caudal fibers of the trapezius indicating that the subclavius is used when the animal must depress, or resist cranial displacement, of the protracted shoulder girdle, while the caudal trapezius is recruited when the girdle is retracted on the chest wall.