科學(xué)家們通過最新的DNA片段發(fā)現(xiàn),，在人類的歷史上同靈長類動物黑猩猩一樣，男性的陰莖是有“刺”的,。但是隨著人類的不斷進(jìn)化,，為了更好的促進(jìn)大腦的發(fā)育，以及更長時間的性交,，男性陰莖上的“刺”逐漸消失了,。科學(xué)家們表示,，這也有助于人類一夫一妻制的形成,。
為了更精確的知曉人類的進(jìn)化史，斯坦福橋大學(xué)的大衛(wèi)-金斯利博士和他的團(tuán)隊一直致力于人類基因?qū)W的研究,。在同其他靈長類動物進(jìn)行對比后，他們發(fā)現(xiàn)了導(dǎo)致男性陰莖中的“刺”消失的基因片段,。
金斯利博士說道：“很多人都會非常驚訝為什么其他雄性動物的陰莖中竟然長有刺,，但實際上人類在進(jìn)化中也是有的，不過部分基因的消失,，使得人類的這些特征逐漸消失,。”這項研究發(fā)表在《自然》雜志上，意在說明基因在控制物種的進(jìn)化中扮演者極其重要的角色,。
金斯利博士研究后發(fā)現(xiàn)與其他的靈長類動物想比,，人類缺失了大約510種基因片段，其中這些基因片段包含控制大腦發(fā)育的基因和雄性激素分泌的基因,。金斯利博士說道：“這些被刪除的基因很多是為了更好的促進(jìn)大腦的發(fā)展,，而其中有部分基因就是關(guān)于‘刺’的，它的消失可以有助于人類進(jìn)行更長時間的性交,。”
“從某種程度上講,，陰莖中‘刺’的消失都是有助于人類進(jìn)化的。水乳交融的性交能夠產(chǎn)生更優(yōu)質(zhì)的后代,，大腦也更為發(fā)達(dá),。”金斯利博士說道。不過,，金斯利博士也發(fā)現(xiàn)了并不是所有基因的消失都是有利的,，比如有些基因消失后人類更容易患上各種疾病，比如關(guān)節(jié)炎,、癌癥,、瘧疾、帕金森綜合癥等,。他說道：“我們會逐漸揭開這些謎題,。”（生物谷Bioon.com）
Nature News： How the penis lost its spikes
生物谷推薦原文出處：
Nature doi:10.1038/nature09774
Human-specific loss of regulatory DNA and the evolution of human-specific traits
Cory Y. McLean,1, 4 Philip L. Reno,2, 3, 4, 5 Alex A. Pollen,2, 4 Abraham I. Bassan,2 Terence D. Capellini,2 Catherine Guenther,2, 3 Vahan B. Indjeian,2, 3 Xinhong Lim,2 Douglas B. Menke,2, 3, 5 Bruce T. Schaar,2 Aaron M. Wenger,1 Gill Bejerano1, 2 & David M. Kingsley2, 3
Humans differ from other animals in many aspects of anatomy, physiology, and behaviour; however, the genotypic basis of most human-specific traits remains unknown1. Recent whole-genome comparisons have made it possible to identify genes with elevated rates of amino acid change or divergent expression in humans, and non-coding sequences with accelerated base pair changes2, 3, 4, 5. Regulatory alterations may be particularly likely to produce phenotypic effects while preserving viability, and are known to underlie interesting evolutionary differences in other species6, 7, 8. Here we identify molecular events particularly likely to produce significant regulatory changes in humans: complete deletion of sequences otherwise highly conserved between chimpanzees and other mammals. We confirm 510 such deletions in humans, which fall almost exclusively in non-coding regions and are enriched near genes involved in steroid hormone signalling and neural function. One deletion removes a sensory vibrissae and penile spine enhancer from the human androgen receptor (AR) gene, a molecular change correlated with anatomical loss of androgen-dependent sensory vibrissae and penile spines in the human lineage9, 10. Another deletion removes a forebrain subventricular zone enhancer near the tumour suppressor gene growth arrest and DNA-damage-inducible, gamma (GADD45G)11, 12, a loss correlated with expansion of specific brain regions in humans. Deletions of tissue-specific enhancers may thus accompany both loss and gain traits in the human lineage, and provide specific examples of the kinds of regulatory alterations6, 7, 8 and inactivation events13 long proposed to have an important role in human evolutionary divergence.
