Genomics and the origin of species
Emergent trends and gaps in understanding are identified, new approaches to more fully integrate genomics into speciation research are proposed, and an integrative definition of the field of speciation genomics is provided.
Evaluating the Use of ABBA–BABA Statistics to Locate Introgressed Loci
It is found that D is unreliable in this situation as it gives inflated values when effective population size is low, causing D outliers to cluster in genomic regions of reduced diversity, and a related statistic a modified version of a statistic originally developed to estimate the genome-wide fraction of admixture is proposed.
Reproductive isolation caused by colour pattern mimicry
It is shown that a shift in colour pattern mimicry was crucial in the origin of two butterfly species, and individuals from a population of H. melpomene allopatric to H. cydno court and mate with the sister species more readily than those from a sympatric population, suggesting that assortative mating has been enhanced in sympatry.
Butterfly genome reveals promiscuous exchange of mimicry adaptations among species
It is inferred that closely related Heliconius species exchange protective colour-pattern genes promiscuously, implying that hybridization has an important role in adaptive radiation.
Genome-wide evidence for speciation with gene flow in Heliconius butterflies
Overall these results show that species divergence can occur in the face of persistent and genome-wide admixture over long periods of time.
Speciation by hybridization in Heliconius butterflies
It is shown that a hybrid trait in an animal species can directly cause reproductive isolation, and that the phenotype of H. heurippa reproductively isolates it from both parental species.
Chromosomal rearrangements maintain a polymorphic supergene controlling butterfly mimicry
The results indicate that allelic combinations at known wing-patterning loci have become locked together in a polymorphic rearrangement at the P locus, forming a supergene that acts as a simple switch between complex adaptive phenotypes found in sympatry.
Linkage Mapping and Comparative Genomics Using Next-Generation RAD Sequencing of a Non-Model Organism
This work constructed a RAD library using genomic DNA from a Plutella xylostella backcross that segregated for resistance to the insecticide spinosad, and used RAD sequencing to construct a genetic linkage map de novo for an organism that has no previous genome data.
Multilocus Species Trees Show the Recent Adaptive Radiation of the Mimetic Heliconius Butterflies
- K. M. Kozak, N. Wahlberg, Andrew F. E. Neild, K. Dasmahapatra, J. Mallet, C. Jiggins
- Biology, Environmental SciencebioRxiv
- 2 April 2014
It is found that the tribe Heliconiini had doubled its rate of speciation around 11 Ma and that the presently most speciose genus Heliconius started diversifying rapidly at 10 Ma, likely in response to the recent drastic changes in topography of the region.
Genomic islands of divergence in hybridizing Heliconius butterflies identified by large-scale targeted sequencing
- N. Nadeau, A. Whibley, C. Jiggins
- BiologyPhilosophical Transactions of the Royal Society B…
- 5 February 2012
Targeted next-generation sequence capture is used to survey patterns of divergence across these entire regions in divergent geographical races and species of Heliconius, finding major peaks of elevated population differentiation between races across hybrid zones, which indicate regions under strong divergent selection.