Journal Articles (Biological Sciences)

2002-01-01

Lewis, Mark A., Bingtuan Li, Hans F. Weinberger

 One crucial measure of a species' invasiveness is the rate at which it spreads into a competitor's environment. A heuristic spread rate formula for a spatially explicit, two-species competition model relies on `linear determinacy' which equates spread rate in the full nonlinear model with spread...

2021-07-06

Jingjing Xu, Evelyn H. Merrill, Mark A. Lewis

Chronic wasting disease (CWD) is a fatal disease of cervid species that continues to spread across North America and now in Europe. It poses a threat to cervid populations and the local ecological and economic communities that depend on them. Although empirical studies have shown that host home...

2012-01-01

Mark A. Lewis, Bingtuan Li

How growth, mortality, and dispersal in a species affect the species' spread and persistence constitutes a central problem in spatial ecology. We propose impulsive reaction-diffusion equation models for species with distinct repro- ductive and dispersal stages. These models can describe a...

2007

Smith, D. W., Anderson, D. P., Ives, A. R., Turner, M. G., Beyer, H. L., Boyce, M. S., Forester, J. D., Fortin, D.

Explaining and predicting animal movement in heterogeneous landscapes remains challenging. This is in part because movement paths often include a series of short, localized displacements separated by longer-distance forays. This multiphasic movement behavior reflects the complex response of an...

2016-01-01

Auger-Méthé, Marie, Field, Chris, Albertsen, Christopher M., Derocher, Andrew E., Lewis, Mark A., Jonsen, Ian D., Mills Flemming, Joanna

State-space models (SSMs) are increasingly used in ecology to model time-series such as animal movement paths and population dynamics. This type of hierarchical model is often structured to account for two levels of variability: biological stochasticity and measurement error. SSMs are flexible....

2014-01-01

Potts, Jonathan R., Mokross, Karl, Stouffer, Philip C., Lewis, Mark A.

Understanding the behavioral decisions behind animal movement and space use patterns is a key challenge for behavioral ecology. Tools to quantify these patterns from movement and animal–habitat interactions are vital for transforming ecology into a predictive science. This is particularly...

2011

Lewis, M. A., Muirhead, J. R., Potapov, A., Lele, S. R.

Freshwater aquatic systems in North America are being invaded by many different species, ranging from fish, mollusks, cladocerans to various bacteria and viruses. These invasions have serious ecological and economic impacts. Human activities such as recreational boating are an important pathway...

2006

Little, S. A., Stockey, R. A., Rothwell, G. W.

The discovery of two anatomically preserved rhizomes with attached stipe bases and adventitious roots contributes to our knowledge of filicalean fern diversity and evolution. Specimens are preserved in marine carbonate nodules at the Lower Cretaceous (Valanginian to Hauterivian) Apple Bay...

1999

Gifford, D. J., Stone, S. L.

Abstract: Triacylglycerols (TAGs) comprised 59% of the total storage reserve in mature loblolly pine (Pinus taeda L.) seeds; 80% of these TAGs were stored in the megagametophyte. The TAG breakdown in the seedling was initiated before radicle emergence (during germination), while in the...

1997

Stone, S. L., Gifford, D. J.

Abstract: Quantitative and qualitative changes in the storage proteins of loblolly pine (Pinus taeda L.) seeds were followed during germination and early-seedling growth and were correlated with light-microscopic observations. In both the megagametophyte and the embryo, the cells of tissues from...