Family values

Evolutionary Genetics (2nd edn) by J. Maynard Smith, Oxford University Press, 1998. £50.00 hbk, £19.95 pbk (368 pages) ISBN 0 19 850232 X/0 19 850231 1Selection in Natural Populations by J.B. Mitton, Oxford University Press, 1998. £50.00 hbk (252 pages) ISBN 0 19 506352 XProgress and Prospects in Evolutionary Biology edited by J.R. Powell, Oxford University Press, 1997. £49.50 hbk (576 pages) ISBN 0 19 507691 5Evolution on Islands edited by P.R. Grant, Oxford University Press, 1997. £24.99 pbk (348 pages) ISBN 0 19 850 1714     

进化细胞生物学的提出及其任务

作者提出应创建一门源于进化生物学与细胞生物学两者的交叉学科一进化细胞生物学(细胞的进化生物学)。其根本任务在于用进化的观点考察真核细胞的一切方面,从它们的起源和演化来认识它们的现在。文中列举了其具体的研究内容,并分析了其研究方法上的特点,指出在这里需要把进化生物学的综合性分析与细胞生物学的实验研究最紧密地结合起来。文中还论述了真核细胞的细胞器的“不进化”现象,指出其根本原因在于进化焦点的转移。     

Hierarchical competition models with the Allee effect II: the case of immigration

ABSTRACT

This is part II of an earlier paper that dealt with hierarchical models with the Allee effect but with no immigration. In this paper, we greatly simplify the proofs in part I and provide a proof of the global dynamics of the non-hyperbolic cases that were previously conjectured. Then, we show how immigration to one of the species or to both would, drastically, change the dynamics of the system. It is shown that if the level of immigration to one or to both species is above a specified level, then there will be no extinction region where both species go to extinction.     

Can revisionism,in evolutionary biology,help in formulating hypotheses about hominid evolution?

While evolutionary theory has been undergoing considerable revision for more than a decade scarcely any biological scientists are willing to resurrect the notion of acquired inheritance since it totally jndermines the concept of ancestor-descendant stability. Acquired inheritance is divisible into two components, soma to germ transfer to replicable information and directed or anticipatory mutation. Pure soma to germ transfer still allows for random events or natural selection as is evident from E. Steel’s proposal of the “somatic selection hypothesis”. Directed mutation is non-stochastic and self-referent. Recent bacterial research has claimed strong support for directed mutation but this phenomenon still would not be important for the small proportion of living taxa (including primates) who sequester their germlines early in ontogeny. There is a basic incompatibility between purposeful responses to final growth stages in complex metazoans and the need to permanently fix future growth into heritable programs. Symposium on Foundations for different approaches to the study of human evolution September 1–3, 1989, Liblice, Czechoslovakia, Czechoslovak Academy of Science     

How Development May Direct Evolution

A framework is presented in which the role ofdevelopmental rules in phenotypic evolution canbe studied for some simple situations. Usingtwo different implicit models of development,characterized by different developmental mapsfrom genotypes to phenotypes, it is shown bysimulation that developmental rules and driftcan result in directional phenotypic evolutionwithout selection. For both models thesimulations show that the critical parameterthat drives the final phenotypic distributionis the cardinality of the set of genotypes thatmap to each phenotype. Details of thedevelopmental map do not matter. If phenotypesare randomly assigned to genotypes, the lastresult can also be proved analytically.     

Extensive evolutionary rate variation in floral color determining genes in the genus Ipomoea

Flower color is an important adaptive trait in many plant species because it determines reproductive success through differential attractiveness to insect pollinators. The genus Ipomoea is a pan tropically distributed plant genus characterized by showy flowers that often differ in color among closely related species. Flower color is determined primarily by products of the anthocyanin biosynthesis pathway. To determine whether flower color evolution among members of the genus is driven by adaptive molecular evolution of the anthocyanin pathway genes, we analyzed data from 10 genes sequenced from 19 species of Ipomoea . Six protein-coding genes from the anthocyanin pathway were drawn for evolutionary analysis in addition to three genes from the unrelated leucine biosynthesis pathway and one MADS box regulatory gene for comparison. The analyses provided: (i) no convincing evidence for positive selection on anthocyanin pathway structural genes, or on the other sampled genes, despite shifts in flower color among species included in the sample; (ii) pathway position correlated weakly with estimates of the intensity of evolutionary constraint on the anthocyanin pathway enzyme coding genes; and (iii) there was substantial gene-specific heterogeneity in the rates of synonymous site evolution. Synonymous rate heterogeneity does not appear to be accounted for by codon bias or local contextual or compositional sequence differences, leading us to implicate heterogeneous rates of mutation among genes as the most probable cause of synonymous rate heterogeneity.     

“It Ain’t Over ‘til it’s Over”: Rethinking the Darwinian Revolution

This paper attempts a critical examination of scholarly understanding of the historical event referred to as the Darwinian Revolution. In particular, it concentrates on some of the major scholarly works that have appeared since the publication in 1979 of Michael Ruses The Darwinian Revolution: Nature Red in Tooth and Claw. The paper closes by arguing that fruitful critical perspectives on what counts as this event can be gained by locating it in a range of historiographic and disciplinary contexts that include the emergence of the discipline of evolutionary biology (following the evolutionary synthesis), the 1959 Darwin centenary, and the maturation of the discipline of the history of science. Broader perspectives on something called the Darwinian Revolution are called for that include recognizing that it does not map a one-to-one correspondence with the history of evolution, broadly construed.     

The Philosophy of Donald T. Campbell: A Short Review and Critical Appraisal

Aside from his remarkable studies in psychology and the social sciences, Donald Thomas Campbell (1916–1996) made significant contributions to philosophy, particularly philosophy of science,epistemology, and ethics. His name and his work are inseparably linked with the evolutionary approach to explaining human knowledge (evolutionary epistemology). He was an indefatigable supporter of the naturalistic turn in philosophy and has strongly influenced the discussion of moral issues (evolutionary ethics). The aim of this paper is to briefly characterize Campbells work and to discuss its philosophical implications. In particular, I show its relevance to some current debates in the intersection of biology and philosophy. In fact, philosophy of biology would look poorer without Campbells influence. The present paper is not a hagiography but an attempt to evaluate and critically discuss the meaning of Campbells work for philosophy of biology and to encourage scholars working in this field to read and re-read this work which is both challenging and inspiring.     

文昌鱼特异的基因倍增

进化生物学和发育生物学的结合产生了一门新兴学科——进化发育生物学,近年来该领域研究取得了丰硕的成果。头索动物文昌鱼是现存生物中最近似于脊椎动物直接祖先的生物,在与脊椎动物分化后形态改变很小,其基因组未曾经历大规模的基因组倍增,在一定程度上反映了脊椎动物祖先型基因组的特征,但在漫长的独立进化历程中基因组自身还是经历了一些变化。本文介绍了在几例在文昌鱼支系中独立发生的基因倍增事件(Hox; Evx; HNF-3; Calmodulin-like),有力地揭示了文昌鱼虽然与脊椎动物直接祖先极其接近,但其基因组有其自身特性,不能简单地将之等同于脊椎动物直接祖先。Abstract: The union of the two complementary disciplines, developmental biology and evolutionary biology resulted in a new division of evolutionary developmental biology, namely “Evo-Devo”. Recently, the research on this field has been fruitful in understanding the origin and development of vertebrates. The cephalochordate amphioxus, which remains in relatively invariant morphology since the divergence from the vertebrate lineage, is the closest living relative to vertebrates. The vertebrate-like simple body plan and preduplicative genome provide amphioxus genes the privilege to serve as key landmark to understand morphological evolution. However, the amphioxus genome has not escaped evolution. In this paper several examples of independent gene (Hox; Evx; HNF-3 and Calmodulin-like) duplications in the cephalochordate lineage were summarized. These particularities and oddities remind the fact that amphioxus is not an immediate ancestor of the vertebrates but ‘only’ the closest living relative to the ancestor, with a mix of prototypical and amphioxus-specific features in its genome.     

花、基因、禾本科

进化发育生物学的一个重要任务就是揭示形态多样性的分子基础,该领域的研究包含形态、形态发育相关基因和形态所属类群等三个要素。花/花序是进化发育生物学研究的首要对象,系统发育重建和个体发育剖析的结合将促进认知花的形态进化。发育相关基因的进化表现为等位基因遗传或表观遗传的突变,基因家族生与死的进化,不同基因组拥有独特的基因。运用形态学或序列分析方法很大程度揭示了禾本科植物花进化过程中的基因进化。试从学科问题、思路方法以及具体例子介绍植物进化发育生物学。