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Niche conservatism above the species level
Elizabeth A Hadly1, Paula A Spaeth, Cheng Li
1Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305-5020, USA. hadly@stanford.edu
Summary
Ecological niches, particularly for mammals, show conservatism above the species level, persisting across major climate changes. This suggests higher taxonomic levels like genera are crucial for biodiversity conservation.
Area of Science:
- Ecology
- Evolutionary Biology
- Paleoclimatology
Background:
- Niche conservatism describes the persistence of ecological traits over time.
- This phenomenon is typically studied at the species level.
Purpose of the Study:
- To investigate niche conservatism at taxonomic levels above species, specifically genera and families of North American mammals.
- To analyze changes in realized niche using geographic range size across the last glacial-interglacial transition.
Main Methods:
- Calculated mean and variance of geographic range size for extant mammalian genera and families.
- Ranked clades by range size and estimated changes during the late Pleistocene and late Holocene.
- Examined range shifts and extinctions within clades.
Main Results:
- Mammalian genera and families exhibited stable range sizes across the glacial-interglacial transition, despite species-level changes.
- Niche conservatism appears consistent at genus and family levels over this period.
- Range size constancy suggests underlying controls differ between species and higher taxonomic levels.
Conclusions:
- Niche conservatism at higher taxonomic levels (genus, family) is influenced by intrinsic life history traits.
- Species-level niche conservatism is more strongly linked to environmental factors.
- Conserving mammal biodiversity requires focusing on genus-level diversity and maintaining species richness within genera.
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