Fertilization modes and the evolution of sperm characteristics in marine fishes: Paired comparisons of externally and internally fertilizing species.
Fertilization modes and the evolution of sperm characteristics in marine fishes: Paired comparisons of externally and internally fertilizing species.
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DOI：
10.1002/ece3.9562
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发表时间：
2022-12
影响因子：
2.6
通讯作者：
中科院分区：
文献类型：
--
作者：
受精方式可能会影响精子的特征，如形态，速度和活力。然而，关于受精模式如何影响精子进化的信息很少，因为有几个因素（例如，精子竞争）是错综复杂地交织在一起时，遗传学上遥远的物种进行比较。在这里，我们调查了精子的特点，比较7个外部和4个内部的海洋鱼类从三个不同的群体含有近亲，考虑精子竞争水平。精子头部显着细长的内部肥料比外部肥料，这表明一个细长的头部是有利的游泳在粘性卵巢液或卵巢狭窄的空间。此外，精子活力之间的外部和内部肥料不同;外部肥料的精子只在海水中活动，而内部肥料的精子只在等渗溶液中活动。这些结果表明，精子活力是根据受精方式进行调整。相比之下，精子总长度和精子速度与受精方式无关，可能是因为精子竞争水平不同。睾丸相对质量（精子竞争水平的指标）与精子运动速度呈正相关，与精子头部长度占精子总长度的比值呈负相关。这些发现表明，精子竞争水平较高的物种具有更快的精子，相对于头部长度，鞭毛更长。这些结果反驳了先前的假设，即内部受精的进化增加了精子的总长度。此外，内授精的交配行为可能涉及一个大的生殖器形态，但这在鱼类中不是必需的，这表明存在各种精子转移方法。虽然我们的分析的力量并不强，因为物种的数量有限，我们提出了一个新的精子进化的情况下，内部受精将增加精子头的长度，但不是总的精子长度，并改变精子活力。我们比较了7个外部和4个内部受精物种的精子特征，以探讨受精方式的进化效应，考虑精子竞争水平。我们发现，内部受精应增加精子头部的长度，但不是总的精子长度，并改变精子活力，而精子竞争应影响精子的长度和速度。我们的发现为鱼类精子的进化生物学提供了新的视角。
Fertilization mode may affect sperm characteristics, such as morphology, velocity, and motility. However, there is little information on how fertilization mode affects sperm evolution because several factors (e.g., sperm competition) are intricately intertwined when phylogenetically distant species are compared. Here, we investigated sperm characteristics by comparing seven externally and four internally fertilizing marine fishes from three different groups containing close relatives, considering sperm competition levels. The sperm head was significantly slenderer in internal fertilizers than in external fertilizers, suggesting that a slender head is advantageous for swimming in viscous ovarian fluid or in narrow spaces of the ovary. In addition, sperm motility differed between external and internal fertilizers; sperm of external fertilizers were only motile in seawater, whereas sperm of internal fertilizers were only motile in an isotonic solution. These results suggest that sperm motility was adapted according to fertilization mode. By contrast, total sperm length and sperm velocity were not associated with fertilization mode, perhaps because of the different levels of sperm competition. Relative testis mass (an index of sperm competition level) was positively correlated with sperm velocity and negatively correlated with the ratio of sperm head length to total sperm length. These findings suggest that species with higher levels of sperm competition have faster sperm with longer flagella relative to the head length. These results contradict the previous assumption that the evolution of internal fertilization increases the total sperm length. In addition, copulatory behavior with internal insemination may involve a large genital morphology, but this is not essential in fish, suggesting the existence of various sperm transfer methods. Although the power of our analyses is not strong because of the limited number of species, we propose a new scenario of sperm evolution in which internal fertilization would increase sperm head length, but not total sperm length, and change sperm motility. We compared sperm characteristics between seven externally and four internally fertilizing species to investigate the evolutionary effect of fertilization mode, considering sperm competition levels. We found that internal fertilization should increase sperm head length, but not total sperm length, and change sperm motility, whereas sperm competition should affect sperm length and velocity. Our findings provide a new perspective on the evolutionary biology of sperm in fishes.
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影响因子：
3.4
作者：
Vicens A;Tourmente M;Roldan ER
通讯作者：
Roldan ER
DOI：
10.1098/rstb.2020.0074
发表时间：
2020-12-07
期刊：
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
影响因子：
--
作者：
Fitzpatrick JL
通讯作者：
Fitzpatrick JL
DOI：
10.1073/pnas.0809990106
发表时间：
2009-01-27
影响因子：
11.1
作者：
Fitzpatrick, John L.;Montgomerie, Robert;Balshine, Sigal
通讯作者：
Balshine, Sigal
影响因子：
1.2
作者：
Akagawa, Izumi;Hara, Masako;Iwamoto, Toshitaka
通讯作者：
Iwamoto, Toshitaka
影响因子：
7.2
作者：
Brennan, Patricia L. R.;Prum, Richard O.
通讯作者：
Prum, Richard O.