Adaptive responses of animals to climate change are most likely insufficient

Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species

Adaptive responses of animals to climate change are most likely insufficient

Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species.Peer reviewe

Indirect estimates of breeding and natal philopatry in an obligate avian brood parasite

In theory, obligate brood parasitic birds are freed from several of the temporal and spatial constraints of parental care for dependent young. Yet, similar to parental bird species, adults in several avian brood parasites show a territorial spacing system while breeding, including site fidelity within and across years. Banding-based capture and sighting studies are also suggestive of non-parasite-like lower levels of natal philopatry in avian brood parasites. We analyzed the potential correlation of physical distance with genetic structure of a Brown-headed Cowbird Molothrus ater population, sampling parasitic chicks from nests across different temporal and spatial scales of its common host, the Eastern Phoebe Sayornis phoebe, near Ithaca, New York, USA. In support of extensive breeding but not historical patterns of natal philopatry, we detected no significant covariation of genetic similarity by distance of nestling parasites at the scale beyond that of individual host nest sites. These results contribute towards a baseline for future behavioral and genetic comparisons of whether and how parasitic versus parental reproductive strategies impact patterns of avian population genetic structure across space and time.Mark E. Hauber, Bill M. Strausberger, Kevin A. Feldheim, Justin Lock, Phillip Casse