TY - JOUR
T1 - Sex dimorphism and evidence of sexually selected traits
T2 - A case study on the killifish Aphaniops stoliczkanus (Day, 1872)
AU - Herbert Mainero, Andrea
AU - Al-Jufaili, Saud M.
AU - Jawad, Laith
AU - Reichenbacher, Bettina
N1 - Publisher Copyright:
© 2022 The Authors. Acta Zoologica published by John Wiley & Sons Ltd on behalf of Royal Swedish Academy of Sciences.
PY - 2022/8/21
Y1 - 2022/8/21
N2 - Sex dimorphism is found in many organisms and is an important source of intraspecific variation. Among freshwater fishes, all members of the Aphaniidae (killifishes, Cyprinodontiformes) are known for their pronounced sex dimorphism, and it has been proposed that sexual selection has played a role in their diversification. However, few studies have assessed their sex dimorphism in detail. Here, we use Aphaniops stoliczkanus (Day, 1872) to analyse morphological variability within and between sexes and within the total sample using statistical analyses of body morphometry, meristic traits and otolith data. We found that sex dimorphism (i) is significant in many body morphometric variables, but (almost) absent in meristic traits and otolith morphometry, (ii) is most marked in anal- and dorsal-fin lengths (larger in males), and in anal- and dorsal-fin positions (more anteriorly positioned in males) and (iii) does not alter the overall variance of the population unless the character concerned is highly divergent. Our data also suggest that anal- and dorsal-fin lengths in males of A. stoliczkanus are sexually selected traits. Together with literature data, this reinforces the idea that sexual selection plays a role in the diversification of aphaniid species. Our results are also relevant to work on fossils, in which morphological variability is often difficult to interpret.
AB - Sex dimorphism is found in many organisms and is an important source of intraspecific variation. Among freshwater fishes, all members of the Aphaniidae (killifishes, Cyprinodontiformes) are known for their pronounced sex dimorphism, and it has been proposed that sexual selection has played a role in their diversification. However, few studies have assessed their sex dimorphism in detail. Here, we use Aphaniops stoliczkanus (Day, 1872) to analyse morphological variability within and between sexes and within the total sample using statistical analyses of body morphometry, meristic traits and otolith data. We found that sex dimorphism (i) is significant in many body morphometric variables, but (almost) absent in meristic traits and otolith morphometry, (ii) is most marked in anal- and dorsal-fin lengths (larger in males), and in anal- and dorsal-fin positions (more anteriorly positioned in males) and (iii) does not alter the overall variance of the population unless the character concerned is highly divergent. Our data also suggest that anal- and dorsal-fin lengths in males of A. stoliczkanus are sexually selected traits. Together with literature data, this reinforces the idea that sexual selection plays a role in the diversification of aphaniid species. Our results are also relevant to work on fossils, in which morphological variability is often difficult to interpret.
KW - Aphaniidae
KW - Aphaniops
KW - morphological variability
KW - sex dimorphism
KW - sexually selected traits
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UR - https://www.mendeley.com/catalogue/04180734-a247-315a-a476-0f11abecf993/
U2 - 10.1111/azo.12436
DO - 10.1111/azo.12436
M3 - Article
AN - SCOPUS:85136457947
SN - 0001-7272
VL - 104
SP - 473
EP - 487
JO - Acta Zoologica
JF - Acta Zoologica
IS - 3
ER -