Limits...
Climate change drives microevolution in a wild bird.

Karell P, Ahola K, Karstinen T, Valkama J, Brommer JE - Nat Commun (2011)

Bottom Line: As winter conditions became milder in the last decades, selection against the brown morph diminished.Concurrent with this reduced selection, the frequency of brown morphs increased rapidly in our study population during the last 28 years and nationwide during the last 48 years.Hence, we show the first evidence that recent climate change alters natural selection in a wild population leading to a microevolutionary response, which demonstrates the ability of wild populations to evolve in response to climate change.

View Article: PubMed Central - PubMed

Affiliation: Bird Ecology Unit, Department of Biosciences, University of Helsinki, PO Box 65 (Viikinkaari 1), Helsinki FI-00014, Finland. patrik.karell@helsinki.fi

ABSTRACT
To ensure long-term persistence, organisms must adapt to climate change, but an evolutionary response to a quantified selection pressure driven by climate change has not been empirically demonstrated in a wild population. Here, we show that pheomelanin-based plumage colouration in tawny owls is a highly heritable trait, consistent with a simple Mendelian pattern of brown (dark) dominance over grey (pale). We show that strong viability selection against the brown morph occurs, but only under snow-rich winters. As winter conditions became milder in the last decades, selection against the brown morph diminished. Concurrent with this reduced selection, the frequency of brown morphs increased rapidly in our study population during the last 28 years and nationwide during the last 48 years. Hence, we show the first evidence that recent climate change alters natural selection in a wild population leading to a microevolutionary response, which demonstrates the ability of wild populations to evolve in response to climate change.

Show MeSH

Related in: MedlinePlus

Frequency distribution of tawny owl colouration in the study population.Colour scoring is based on scorings of brown pigmentation on four different parts of the plumage and ranges from 4 to 14 points in 491 individuals scored in 1978–2008. The frequency of colouration is bimodal and the two morphs can be classified into a grey and a brown morph at the cut point between scores 9 and 10. The cut point (red line) was determined visually as the lowest intermediate point between the two models18. A grey (left) and a brown (right) tawny owl colour morph are shown above the graph (photography courtesy of: Dick Forsman).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3105316&req=5

f1: Frequency distribution of tawny owl colouration in the study population.Colour scoring is based on scorings of brown pigmentation on four different parts of the plumage and ranges from 4 to 14 points in 491 individuals scored in 1978–2008. The frequency of colouration is bimodal and the two morphs can be classified into a grey and a brown morph at the cut point between scores 9 and 10. The cut point (red line) was determined visually as the lowest intermediate point between the two models18. A grey (left) and a brown (right) tawny owl colour morph are shown above the graph (photography courtesy of: Dick Forsman).

Mentions: In this study, we explore the links between climate change and alteration of the selective regime on a highly heritable phenotypic trait, plumage colouration in the tawny owl (Strix aluco), a common bird of prey throughout the temperate regions of Europe. In tawny owls, plumage colouration is determined by the degree of reddish-brown pheomelanin pigmentation deposited in their plumage17. This colouration is independent of age and sex, and is highly heritable18. The frequency distribution of colouration (scored on an ordinal scale) shows a bimodal distribution (Fig. 1), suggesting there are two basic morphs (termed grey and brown). Earlier work revealed that the brown tawny owl morph has reduced survival compared with the grey morph, resulting in lower lifetime reproductive success of the brown morph18.


Climate change drives microevolution in a wild bird.

Karell P, Ahola K, Karstinen T, Valkama J, Brommer JE - Nat Commun (2011)

Frequency distribution of tawny owl colouration in the study population.Colour scoring is based on scorings of brown pigmentation on four different parts of the plumage and ranges from 4 to 14 points in 491 individuals scored in 1978–2008. The frequency of colouration is bimodal and the two morphs can be classified into a grey and a brown morph at the cut point between scores 9 and 10. The cut point (red line) was determined visually as the lowest intermediate point between the two models18. A grey (left) and a brown (right) tawny owl colour morph are shown above the graph (photography courtesy of: Dick Forsman).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3105316&req=5

f1: Frequency distribution of tawny owl colouration in the study population.Colour scoring is based on scorings of brown pigmentation on four different parts of the plumage and ranges from 4 to 14 points in 491 individuals scored in 1978–2008. The frequency of colouration is bimodal and the two morphs can be classified into a grey and a brown morph at the cut point between scores 9 and 10. The cut point (red line) was determined visually as the lowest intermediate point between the two models18. A grey (left) and a brown (right) tawny owl colour morph are shown above the graph (photography courtesy of: Dick Forsman).
Mentions: In this study, we explore the links between climate change and alteration of the selective regime on a highly heritable phenotypic trait, plumage colouration in the tawny owl (Strix aluco), a common bird of prey throughout the temperate regions of Europe. In tawny owls, plumage colouration is determined by the degree of reddish-brown pheomelanin pigmentation deposited in their plumage17. This colouration is independent of age and sex, and is highly heritable18. The frequency distribution of colouration (scored on an ordinal scale) shows a bimodal distribution (Fig. 1), suggesting there are two basic morphs (termed grey and brown). Earlier work revealed that the brown tawny owl morph has reduced survival compared with the grey morph, resulting in lower lifetime reproductive success of the brown morph18.

Bottom Line: As winter conditions became milder in the last decades, selection against the brown morph diminished.Concurrent with this reduced selection, the frequency of brown morphs increased rapidly in our study population during the last 28 years and nationwide during the last 48 years.Hence, we show the first evidence that recent climate change alters natural selection in a wild population leading to a microevolutionary response, which demonstrates the ability of wild populations to evolve in response to climate change.

View Article: PubMed Central - PubMed

Affiliation: Bird Ecology Unit, Department of Biosciences, University of Helsinki, PO Box 65 (Viikinkaari 1), Helsinki FI-00014, Finland. patrik.karell@helsinki.fi

ABSTRACT
To ensure long-term persistence, organisms must adapt to climate change, but an evolutionary response to a quantified selection pressure driven by climate change has not been empirically demonstrated in a wild population. Here, we show that pheomelanin-based plumage colouration in tawny owls is a highly heritable trait, consistent with a simple Mendelian pattern of brown (dark) dominance over grey (pale). We show that strong viability selection against the brown morph occurs, but only under snow-rich winters. As winter conditions became milder in the last decades, selection against the brown morph diminished. Concurrent with this reduced selection, the frequency of brown morphs increased rapidly in our study population during the last 28 years and nationwide during the last 48 years. Hence, we show the first evidence that recent climate change alters natural selection in a wild population leading to a microevolutionary response, which demonstrates the ability of wild populations to evolve in response to climate change.

Show MeSH
Related in: MedlinePlus