Department of Chemistry, Emory University, Atlanta, GA 30322, USA.
School of Pharmacy, Hampton University, Hampton, VA 23669, USA.
Molecules. 2021 Oct 31;26(21):6618. doi: 10.3390/molecules26216618.
An extension of neo-Darwinism, termed preassembly, states that genetic material required for many complex traits, such as echolocation, was present long before emergence of the traits. Assembly of genes and gene segments had occurred over protracted time-periods within large libraries of non-coding genes. Epigenetic factors ultimately promoted transfers from noncoding to coding genes, leading to abrupt formation of the trait via de novo genes. This preassembly model explains many observations that to this present day still puzzle biologists: formation of super-complexity in the absence of multiple fossil precursors, as with bat echolocation and flowering plants; major genetic and physical alterations occurring in just a few thousand years, as with housecat evolution; lack of precursors preceding lush periods of species expansion, as in the Cambrian explosion; and evolution of costly traits that exceed their need during evolutionary times, as with human intelligence. What follows in this paper is a mechanism that is not meant to supplant neo-Darwinism; instead, preassembly aims to supplement current ideas when complexity issues leave them struggling.
新达尔文主义的一种延伸,称为预组装,它指出,许多复杂特征(如回声定位)所需的遗传物质在特征出现之前很久就已经存在了。基因和基因片段的组装是在大型非编码基因文库中经过长时间的过程发生的。表观遗传因素最终促进了从非编码基因到编码基因的转移,导致通过从头基因突然形成特征。这个预组装模型解释了许多直到今天仍然困扰着生物学家的观察结果:在没有多个化石前体的情况下形成超级复杂性,就像蝙蝠的回声定位和开花植物一样;在几千年的时间内发生重大的遗传和物理变化,就像家猫的进化一样;在物种扩张的繁荣时期之前没有前体,就像寒武纪大爆发一样;以及昂贵特征的进化超过了它们在进化时期的需要,就像人类智力一样。本文接下来介绍的机制并不是要取代新达尔文主义;相反,当复杂问题使它们难以解决时,预组装旨在补充当前的观点。