Open AccessTesting the hybrid superiority hypothesis in crested and marbled newts
Author(s) -
Cogălniceanu Dan,
Stănescu Florina,
Arntzen Jan W.
Publication year - 2020
Publication title -
journal of zoological systematics and evolutionary research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.769
H-Index - 50
eISSN - 1439-0469
pISSN - 0947-5745
DOI - 10.1111/jzs.12322
Subject(s) - biology , triturus , hybrid , sexual maturity , zoology , hybrid zone , snout , heterosis , morphometrics , ecology , evolutionary biology , botany , genetics , genetic variation , gene flow , gene
We tested the hybrid superiority hypothesis in the zone of overlap and hybridization of the newts Triturus cristatus and T. marmoratus . To do so, we compared size, age, and growth‐related parameters in F 1 hybrids and both parental species in Mayenne, France. We found significant differences in snout‐vent length (SVL), body mass and average lifespan between the parental species and hybrids, increasing from T. cristatus – T. marmoratus – hybrids. The relation between age and SVL fitted von Bertalanffy's growth model and showed that SVL ma x was significantly larger in hybrids than in the parental species, while the growth coefficient was lower in hybrids and T. marmoratus than in T. cristatus . Triturus cristatus appears to be the better competitor, since it attains sexual maturity faster and thus achieves more annual breeding opportunities. At the evolutionary level, the observed heterosis appears not to have further consequences as the hybrids are largely infertile. Our results support the hypothesis raised for the genus Triturus , that infertile hybrids allocate resources to growth.