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Published on: December 25, 2016
"Sexual" behavior in parthenogenetic lizards (Cnemidophorus)
1Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138.
Summary
Parthenogenetic lizards exhibit courtship behaviors similar to sexual species. This behavior may be a vestige of ancestry or essential for reproduction in these all-female species.
Area of Science:
- * Reproductive biology
- * Evolutionary biology
- * Behavioral ecology
Background:
- * Parthenogenetic species, which reproduce asexually, offer unique insights into the evolution of sexual reproduction.
- * Limited behavioral data exists for parthenogenetic organisms, hindering a full understanding of their reproductive strategies.
Purpose of the Study:
- * To investigate and document the behavioral patterns of all-female, parthenogenetic lizard species.
- * To compare the observed behaviors with those of closely related sexual species.
- * To explore the potential functional significance of these behaviors in parthenogens.
Main Methods:
- * Observations were conducted on captive individuals of three parthenogenetic lizard species: *Cnemidophorus uniparens*, *C. velox*, and *C. tesselatus*.
- * Behavioral interactions, specifically mounting and cloacal apposition, were recorded in paired housing.
- * Reproductive status of individuals involved in observed behaviors was assessed through dissection or palpation, examining ovarian follicle development.
Main Results:
- * Parthenogenetic lizards displayed behaviors analogous to courtship and copulation seen in sexual species.
- * In observed interactions, the 'courted' lizard was reproductively active with preovulatory follicles.
- * The 'courting' lizard was reproductively inactive or postovulatory, with undeveloped follicles.
Conclusions:
- * The observed courtship-like behaviors in parthenogenetic lizards are remarkably similar to those in sexual relatives.
- * The function of this behavior in parthenogens remains to be determined; it could be a nonfunctional evolutionary remnant or play a role in reproductive priming.
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