Competitive consequences determined by phenotypic but not genetic distance: a study with asexual water flea genotypes.
Competitive consequences determined by phenotypic but not genetic distance: a study with asexual water flea genotypes.
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由表型而不是遗传距离决定的竞争后果：一项无性水蚤基因型的研究。
DOI：
10.1111/1365-2435.14105
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
J. Urabe
中科院分区：
文献类型：
--
作者：
Tian;X.;H. Ohtsuki;J. Urabe
进化相关性如何影响遗传隔离种群之间竞争相互作用的强度一直是生态学的长期兴趣。达尔文的“竞争相关性假说（CRH）”指出，由于密切相关的物种应该竞争更激烈，它们不太可能共存，而赫伯特的“双峰竞争假说（BCH）”预测，当竞争物种在遗传上接近或远离时，竞争排斥不太可能发生。为了验证这些假设，本文通过实验研究了从同一祖先基因型分化而来的四种不同无性繁殖蚤基因型在生殖力和存活力竞争能力和生命表上的差异，结果表明，不同基因型之间的竞争结果不同，这取决于竞争基因型的配对，并且当竞争基因型在遗传上彼此更接近时，竞争排除的程度较低。这些结果部分支持了BCH，但根本不支持CRH。更重要的是，竞争排斥的程度更好地预测的表型，而不是竞争基因型之间的遗传距离。生命表实验表明，竞争劣势基因型有较高的早期繁殖率，但存活率随着年龄的增长，从而身体大小下降，可能是自然界中捕食压力选择的结果。这些结果表明，竞争优势高度依赖于选择压力，给定的生物已经受到进化，遗传相似性不一定是一个适当的措施，用于预测生态时间尺度上的完全排除。为了预测生物之间的竞争关系，理解它们的表型差异而不是简单地知道它们的遗传或系统发育关系是至关重要的。
How evolutionary relatedness influences the strength of competitive interactions among genetically isolated populations has been a long‐standing interest in ecology. Darwin's ‘Competition‐Relatedness Hypothesis (CRH)’ states that, since closely related species should compete more strongly, they are less likely to coexist, while Herbert's ‘Bimodal Competition Hypothesis (BCH)’ predicts that competitive exclusion is less likely to occur when the competing species are genetically close or distant.To test these hypotheses, we experimentally examined the difference in the competitive ability and life tables of fecundity and survivorship among four different genotypes of asexualDaphniacf.pulexthat diverged from a single ancestral genotype.The experiments showed that the competitive consequences differed depending on the pairing of the competing genotypes, and that the degree of the competitive exclusion was lower when the competing genotypes were genetically closer to each other. These results partially supported the BCH but not the CRH at all. More importantly, the degree of competitive exclusion was better predicted by the phenotypic rather than genetic distances between the competing genotypes.The life table experiments revealed that competitively inferior genotypes had higher early reproduction rates, but survival rates decreased with age and thus body size, probably a result of selection by predation pressures found in nature.These results indicate that competitive superiority is highly dependent on selection pressures that given organisms have been evolutionally subjected to, and, that genetic similarity is not necessarily an appropriate measure for predicting the completive exclusion on an ecological time‐scale. To predict competitive relationships among the organisms, it is essential to comprehend their phenotypic differences rather than simply knowing their genetic or phylogenetic relationships.Read the free Plain Language Summary for this article on the Journal blog.