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  • Repeated independent origins of the placenta reveal convergent and divergent organ evolution within a single fish family (Poeciliidae)
Title: Repeated independent origins of the placenta reveal convergent and divergent organ evolution within a single fish family (Poeciliidae)
An outstanding question in biology is to what extent convergent evolution produces similar, but not necessarily identical, complex phenotypic solutions. The placenta is a complex organ that repeatedly evolved in the livebearing fish family Poeciliidae. Here, we apply comparative approaches to test whether evolution has produced similar or different placental phenotypes in the Poeciliidae and to what extent these phenotypes correlate with convergence at the molecular level. We show the existence of two placental phenotypes characterized by distinctly different anatomical adaptations (divergent evolution). Furthermore, each placental phenotype independently evolved multiple times across the family, providing evidence for repeated convergence. Moreover, our comparative genomic analysis revealed that the genomes of species with different placentas are evolving at a different pace. Last, we show that the two placental phenotypes correlate with two previously described contrasting life-history optima. Our results argue for high evolvability (both divergent and convergent) of the placenta within a group of closely related species in a single family.  more » « less
Award ID(s):
1754669
PAR ID:
10515546
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
34
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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