R. Brian Langerhans
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
R. Brian Langerhans has a total of 4 co-authors. Here are the top co-authors by number of shared publications:
Everton O. Joseph
College of the Bahamas, PO Box N-4912, Nassau, Bahamas
1 shared publicationL. J. Chapman
Biology Department, McGill University, Montreal, QC, Canada
1 shared publication- Matthew E. Gifford
Department of Biology, University of Central Arkansas, Conway, Arkansas, 72034, USA
1 shared publication T. J. Dewitt
Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
1 shared publication
Latest Publications
- Open Access
- 25 July 2007
- Published by Oxford University Press (OUP) in Evolution
- Vol. 61 (9) , 2056-2074
ECOLOGICAL SPECIATION IN GAMBUSIA FISHES
Although theory indicates that natural selection can facilitate speciation as a by-product, demonstrating ongoing speciation via this by-product mechanism in nature has proven difficult. We examined morphological, molecular, and behavioral data to investigate ecology's role in incipient speciation for a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes. We show that adaptation to divergent predator regimes is driving ecological speciation as a by-product. Divergence in body shape, coupled with assortative mating for body shape, produces reproductive isolation that is twice as strong between populations inhabiting different predator regimes than between populations that evolved in similar ecological environments. Gathering analogous data on reproductive isolation at the interspecific level in the genus, we find that this mechanism of speciation may have been historically prevalent in Gambusia. These results suggest that speciation in nature can result as a by-product of divergence in ecologically important traits, producing interspecific patterns that persist long after speciation events have completed.
- 25 July 2007
- Published by Oxford University Press (OUP) in Evolution
- Vol. 61 (9) , 2056-2074
Open AccessECOLOGICAL SPECIATION IN GAMBUSIA FISHES
Although theory indicates that natural selection can facilitate speciation as a by-product, demonstrating ongoing speciation via this by-product mechanism in nature has proven difficult. We examined morphological, molecular, and behavioral data to investigate ecology's role in incipient speciation for a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes. We show that adaptation to divergent predator regimes is driving ecological speciation as a by-product. Divergence in body shape, coupled with assortative mating for body shape, produces reproductive isolation that is twice as strong between populations inhabiting different predator regimes than between populations that evolved in similar ecological environments. Gathering analogous data on reproductive isolation at the interspecific level in the genus, we find that this mechanism of speciation may have been historically prevalent in Gambusia. These results suggest that speciation in nature can result as a by-product of divergence in ecologically important traits, producing interspecific patterns that persist long after speciation events have completed.
- 2 April 2007
- Published by Oxford University Press (OUP) in Journal of Evolutionary Biology
- Vol. 20 (3) , 1171-1181
Complex phenotype–environment associations revealed in an East African cyprinid
Environmental factors influence phenotypes directly, as well as indirectly via trait correlations and interactions with other environmental variables. Using nine populations of the African cyprinidBarbus neumayeri, we employed path analysis to examine direct, indirect and total effects of two environmental variables, water flow (WF) and dissolved oxygen (DO), on several morphological traits. WF and DO directly influenced relative gill size, body shape and caudal fin shape in manners consistent witha prioripredictions. Indirect effects also played an important role in the system: (1) strong, oppositely signed direct and indirect effects of WF on body shape resulted in a nonsignificant total effect; (2) DO had no direct effect on body shape, but a strong total effect via indirect effects on gill size; (3) WF indirectly influenced gill size via effects on DO. Only through examination of multiple environmental parameters and multiple traits can we hope to understand complex relationships between environment and phenotype.
- 2 April 2007
- Published by Oxford University Press (OUP) in Journal of Evolutionary Biology
- Vol. 20 (3) , 1171-1181
Complex phenotype–environment associations revealed in an East African cyprinid
Environmental factors influence phenotypes directly, as well as indirectly via trait correlations and interactions with other environmental variables. Using nine populations of the African cyprinidBarbus neumayeri, we employed path analysis to examine direct, indirect and total effects of two environmental variables, water flow (WF) and dissolved oxygen (DO), on several morphological traits. WF and DO directly influenced relative gill size, body shape and caudal fin shape in manners consistent witha prioripredictions. Indirect effects also played an important role in the system: (1) strong, oppositely signed direct and indirect effects of WF on body shape resulted in a nonsignificant total effect; (2) DO had no direct effect on body shape, but a strong total effect via indirect effects on gill size; (3) WF indirectly influenced gill size via effects on DO. Only through examination of multiple environmental parameters and multiple traits can we hope to understand complex relationships between environment and phenotype.