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Latitudinal gradients in population growth do not reflect demographic responses to climate.

ABSTRACT: Spatial gradients in population growth, such as across latitudinal or elevational gradients, are often assumed to primarily be driven by variation in climate, and are frequently used to infer species' responses to climate change. Here, we use a novel demographic, mixed-model approach to dissect the contributions of climate variables vs. other latitudinal or local site effects on spatiotemporal variation in population performance in three perennial bunchgrasses. For all three species, we find that performance of local populations decreases with warmer and drier conditions, despite latitudinal trends of decreasing population growth toward the cooler and wetter northern portion of each species' range. Thus, latitudinal gradients in performance are not predictive of either local or species-wide responses to climate. This pattern could be common, as many environmental drivers, such as habitat quality or species' interactions, are likely to vary with latitude or elevation, and thus influence or oppose climate responses.

SUBMITTER: DeMarche ML

PROVIDER: S-EPMC7988552 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Latitudinal gradients in population growth do not reflect demographic responses to climate.

DeMarche Megan L ML Bailes Graham G Hendricks Lauren B LB Pfeifer-Meister Laurel L Reed Paul B PB Bridgham Scott D SD Johnson Bart R BR Shriver Robert R Waddle Ellen E Wroton Hannah H Doak Daniel F DF Roy Bitty A BA Morris William F WF

Ecological applications : a publication of the Ecological Society of America 20210118 2

Spatial gradients in population growth, such as across latitudinal or elevational gradients, are often assumed to primarily be driven by variation in climate, and are frequently used to infer species' responses to climate change. Here, we use a novel demographic, mixed-model approach to dissect the contributions of climate variables vs. other latitudinal or local site effects on spatiotemporal variation in population performance in three perennial bunchgrasses. For all three species, we find tha ...[more]

PMID: 33098736

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Latitudinal gradients in population growth do not reflect demographic responses to climate.

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Latitudinal gradients in population growth do not reflect demographic responses to climate.

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