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Diversity among taxodiaceous conifers: Metasequoia foxii sp. nov. from the Paleocene of central Alberta, Canada.
Download2001
Falder, A.B., Stockey, R.A., Rothwell, G.W.
A single species of taxodioid conifers is among the dominant floristic elements at two stratigraphically contemporaneous Paleocene fossil localities in central Alberta, Canada. More than 10,000 compression specimens, including oppositely branched stems, vegetative shoots with decussately arranged...
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2006-01-01
McCauley, E., Lewis, Mark A., Lutscher, F.
The question how aquatic populations persist in rivers when individuals are constantly lost due to downstream drift has been termed the “drift paradox.” Recent modeling approaches have revealed diffusion-mediated persistence as a solution. We study logistically growing populations with and...
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1989
Vegetative and fertile frond segments of Botrychium have been recovered from Paleocene deposits of central Alberta, Canada. Specimens are preserved as coalified compressions that yield information about frond structure, sporangia, and spore ultrastructure. These fossils, described as Botrychium...
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1983
Fossil seedlings and seeds of an extinct Cercidiphyllum-like plant occur in the Paskapoo Formation (Late Paleocene) at Joffre Bridge near Red Deer, Alberta. Cotyledon and early seedling leaf stages are preserved in growth position. Morphological details of seedlings and seeds support a close...
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In situ fossil seedlings of a Metasequoia-like taxodiaceous conifer from Paleocene river floodplain deposits of central Alberta, Canada
Download1999
Stockey, R.A., Faldner, A.B., Rothwell, G.W.
Fossil seeds and seedlings of a Metasequoia-like taxodiaceous conifer occur in Paleocene deposits at the Munce’s Hill and Gao Mine localities of central Alberta, Canada. Compression/impression specimens are preserved in upright growth positions among seedlings of the cercidiphyllaceous dicot...
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Linking occurrence and fitness to persistence: habitat-based approach for endangered greater sage-grouse
Download2007
Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate...
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2008
De-Camino-Beck, T., Lewis, M.A.
Understanding the relationship between life-history patterns and population growth is central to demographic studies. Here we derive a new method for calculating the timing of reproductive output, from which the generation time and its variance can also be calculated. The method is based on the...
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Speirseopteris orbiculata gen. et sp. nov. (Thelypteridaceae), a derived fossil filicalean from the Paleocene of western North America.
Download2006
Stockey, R.A., Rothwell, G.W., Lantz, T.C.
An apparently exindusiate filicalean fern with radial sori, sporangia with a vertical annulus, and monolete spores occurs in Paleocene sediments ca. 57 million years old of central Alberta, Canada. Specimens are preserved as coalified compressions and show features of frond morphology and...