AbstractI am interested generally in the forces that shape the evolution of plants, and more
specifically in plant reproduction. Unlike most animals, the vast majority of plant
individuals possess both female and male sexual organs. This raises a number of interesting
issues: How much should an individual self-fertilize? Does self-fertilization cause
populations to go extinct? In addition to their use in addressing these kinds of questions,
plants are also very useful for addressing other issues of fundamental importance
to evolutionary biology, not just plant evolutionary biology. Such topics include:
the rate of appearance of new, harmful mutations; the effect of continued inbreeding
on fitness; differences in rates of evolution between genes transmitted maternally
vs. paternally; etc., etc.
We have recently discovered that a sperm transmits more mutations than an egg (Whittle
and Johnston, 2002, 2003), and several projects are underway to understand the extent
and causes of this phenomenon.
We use a variety of techniques to study these sorts of questions, including: field
work; greenhouse propagation; the lab work (e.g., DNA sequencing, AFLPs, image analysis,
electron and confocal microscopy, etc.); and theoretical modeling. Graduate training
emphasizes the concepts of evolutionary ecology and evolutionary genetics, as well
as the statistical analysis of data.
My teaching reflects my interests in evolution and ecology, and all my undergraduate
courses are approached from these disciplines. I have also offered modules in topics
such as, a) Ecology and Evolution of plant populations; b) Morphormetrics and c) Mutations
<h2>Mark Johnston, AB (Harvard), PhD (Chicago)</h2>
<p><b>Email</b>: <a href="mailto:firstname.lastname@example.org">email@example.com</a></br><b>Phone</b>: 902-494-8005</br><b>Fax</b>: 902-494-3736</br></p>
<a href="http://dalspace.library.dal.ca/handle/10222/22302/browse?order=DESC&rpp=20&sort_by=2&etal=-1&offset=0&type=dateissued">View Mark Johnston's Publications Sorted by Date</a>