Evolution is inherently a multivariate process,with a complex suite of traits is the focus of natural selection.While virtually every trait shows heritable variation (and hence the potential to respond to selection),evolutionary stasis is not uncommon.We review recent laboratory evidence that suggests that while individual traits may indeed show heritable variation,there is often very little variation along the multivariate direction favored by natural selection.We suggest that such multivariate constraints are common and indeed the wealth of heritable variation in just about any trait can be viewed as a direct consequence of such multivariate constraints.
展开▼
