Evol Ecol Res 3: 345-360 (2001)     Full PDF if your library subscribes.

The latitudinal gradient of diversity through the Holocene as recorded by fossil pollen in Europe

John Haskell

Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA

Address all correspondence to John Haskell, Department of Fisheries and Wildlife, College of Natural Resources, Utah State University, 5210 Old Main Hill, Logan, UT 84322-5210, USA.
e-mail: jhaskell@nutcracker.unm.edu


To assess the impacts of Pleistocene glaciation on the latitudinal diversity gradient, I examined plant family diversity during the last interglacial at 24 sites in Europe between 39° and 71°N latitude. Familial richness and turnover were calculated for 1000-year intervals for each site. Although familial turnover varied from 6 to 59% per 1000 years, familial richness remained essentially constant at 16 (67%) of the sites. For the remaining sites, the rates of change of richness were very low (2–3 families per 1000 years) and were not associated with latitude. These results do not support ‘historical’ hypotheses for the latitudinal diversity gradient, because neither local species richness nor the slope of the gradient have changed meaningfully in the last 10,000 years. Instead, they support hypotheses that invoke contemporary mechanisms to explain the inverse relationship between latitude and diversity. Additionally, the lack of change both in richness at individual sites and in the latitudinal diversity gradient through time suggest that the ecological and evolutionary processes that regulate diversity within local communities operate in a systematic fashion across large spatial and temporal scales. Future hypotheses for the latitudinal gradient of diversity should include universal rules that determine how resources are divided among species at local and global scales without regard to the identify of particular species.

Keywords: community ecology, fossil pollen, latitude, plants, regulation, richness.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 2001 John Haskell. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.