ECOLOGICAL SPECIATION IN STICKLEBACKS: ENVIRONMENT‐DEPENDENT HYBRID FITNESS

@article{Hatfield1999ECOLOGICALSI,
  title={ECOLOGICAL SPECIATION IN STICKLEBACKS: ENVIRONMENT‐DEPENDENT HYBRID FITNESS},
  author={Todd Hatfield and Dolph Schluter},
  journal={Evolution},
  year={1999},
  volume={53}
}
“Ecological” speciation occurs when reproductive isolation evolves as a consequence of divergent selection between populations exploiting different resources or environments. We tested this hypothesis of speciation in a young stickleback species pair by measuring the direct contribution of ecological selection pressures to hybrid fitness. The two species (limnetic and benthic) are strongly differentiated morphologically and ecologically, whereas hybrids are intermediate. Fitness of hybrids is… 

A TEST OF ECOLOGICALLY DEPENDENT POSTMATING ISOLATION BETWEEN SYMPATRIC STICKLEBACKS

  • H. Rundle
  • Environmental Science
    Evolution; international journal of organic evolution
  • 2002
A reversal of relative fitness of the two cross‐types in the two environments provides strong evidence that divergent natural selection has played a central role in the evolution of postmating isolation between Benthics and Limnetics.

Ecological selection against hybrids in natural populations of sympatric threespine sticklebacks

Testing for selection against naturally occurring hybrids in two sympatric species pairs of benthic and limnetic threespine sticklebacks revealed a decline in mean individual hybridity, providing compelling evidence that extrinsic selection plays an important role in maintaining species divergence and supports a role for ecological speciation in stickleback.

Divergent natural selection drives the evolution of reproductive isolation in an Australian wildflower

Natural selection can create strong reproductive barriers that maintain differentiation between populations with the potential to interbreed, and implies a significant role for ecology in the evolutionary divergence of S. lautus.

Adaptive divergence and the evolution of hybrid phenotypes in threespine stickleback

It is demonstrated that some aspects of hybrid phenotypes evolve predictably as parental populations diverge, and evidence is found for a possible general mechanistic link between ecological divergence and reproductive isolation—that more divergent parent populations tend to produce hybrids with novel and potentially deleterious multivariate phenotypes.

Ecological outcomes of hybridization vary extensively in Catostomus fishes

It is suggested that ecological outcomes of hybridization are likely to vary across locations where a pair of species hybridizes, and this variation implies that hybridization might have large unpredictable, idiosyncratic ecological effects on fish assemblages where hybrids occur.

A test of ecological selection against young-ofthe-year hybrids of sympatric sticklebacks

  • V. S.M
  • Environmental Science
  • 2000
Ecological selection against hybrids, the reduction in hybrid fitness attributed solely to environmental factors, was tested by introducing young-of-the-year benthic, limnetic and F1 hybrid

FREQUENCY DEPENDENT NATURAL SELECTION DURING CHARACTER DISPLACEMENT IN STICKLEBACKS

  • D. Schluter
  • Biology, Environmental Science
    Evolution; international journal of organic evolution
  • 2003
Results provide further support for the hypothesis of character displacement in sympatric sticklebacks and suggest that displacement along the resource gradient also led to divergence in vulnerability to agents of mortality, probably including predation.

Ecological speciation in Senecio lautus

The experimental results demonstrate that interfertile plant populations adapting to contrasting environments may diverge as a consequence of concurrent natural selection acting against migrants and hybrids through multiple mechanisms, and suggest that herbivory may play an important role in the early stages of plant speciation.

Heterosis counteracts hybrid breakdown to forestall speciation by parallel natural selection

In contrast to ecological speciation, where reproductive isolation evolves as a consequence of divergent natural selection, speciation by parallel natural selection has been less thoroughly studied.

Ecological Reproductive Isolation of Coast and Inland Races of Mimulus guttatus

Analysis of the population structure and reproductive isolation between coastal perennial and inland annual forms of the yellow monkeyflower suggests that adaptations to widespread habitats can lead to the formation of reproductively isolated species.
...

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