（图片来源：David Haring/Duke University Lemur Center）
生物谷报道：美国科学家在16日的Science发表论文称：灵长类在攀爬时与在行走时，身体大小与能耗相联系的机制是不同的，这可能表明了，为什么早期的灵长类在涌入特别的生境时无需花费攀爬所用的新的代谢成本。
研究人员说，灵长类垂直攀爬所用的能量并不会因为其身材的大小而增减，相反，其所用的能量似乎与其体重无关。另一方面，实际上，灵长类以直线行走所需的能量却会随着其体型的增加而降低，这意味着，较大的灵长类停留在地面上是很有道理的；而就代谢水平来说，较小的灵长类究竟是行走还是攀爬都无足轻重。这些发现与所提出的最早的灵长类是小型灵长类这一理论是一致的。（生物谷www.bioon.com）
生物谷推荐原始出处：
Science，Vol. 320. no. 5878, p. 898，Jandy B. Hanna，Timothy M. Griffin
The Energetic Cost of Climbing in Primates
Jandy B. Hanna,1* Daniel Schmitt,1 Timothy M. Griffin2
Primates are exceptional among mammals for their climbing abilities and arboreal lifestyles. Here we show that small primates (less than 0.5 kilogram) consume the same amount of mass-specific energy (COTTOT) whether climbing or walking a given distance. COTTOT decreases with increasing body size for walking but does not change for climbing. This divergence of COTTOT is likely due to fundamental differences in the biomechanical determinants of the costs of climbing versus walking. These results have important implications for understanding the origins of primates, suggesting that small early primates may have been able to move into a novel arboreal niche without increasing metabolic costs.
