Send to

Choose Destination
Sci Rep. 2016 Feb 12;6:21029. doi: 10.1038/srep21029.

Empirical evidence for large X-effects in animals with undifferentiated sex chromosomes.

Author information

Department of Ecology and Evolution (DEE), University of Lausanne, Biophore, CH-1015 Lausanne, Switzerland.
Department of Evolutionary Biology and Conservation of Vertebrates, Wrocław University, Sienkiewicza 21, 50-335 Wrocław, Poland.
Department of Population Biology, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, External research facility Studenec, 675 02 Koněšín, Czech Republic.
Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301, D-12587 Berlin, Germany.
Laboratory of Behavioral Ecology and Evolution, School of Biological Sciences, Seoul National University, 151-747 Seoul, Republic of Korea.


Reproductive isolation is crucial for the process of speciation to progress. Sex chromosomes have been assigned a key role in driving reproductive isolation but empirical evidence from natural population processes has been restricted to organisms with degenerated sex chromosomes such as mammals and birds. Here we report restricted introgression at sex-linked compared to autosomal markers in a hybrid zone between two incipient species of European tree frog, Hyla arborea and H. orientalis, whose homologous X and Y sex chromosomes are undifferentiated. This large X-effect cannot result from the dominance or faster-X aspects of Haldane's rule, which are specific to degenerated sex chromosomes, but rather supports a role for faster-heterogametic-sex or faster-male evolutionary processes. Our data suggest a prominent contribution of undifferentiated sex chromosomes to speciation.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center