Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support

The Ecological Relationship of the Salamander Ambystoma laterale to its All-Female, Gynogenetic Associate

Henry M. Wilbur
Evolution
Vol. 25, No. 1 (Mar., 1971), pp. 168-179
DOI: 10.2307/2406509
Stable URL: http://www.jstor.org/stable/2406509
Page Count: 12
  • Read Online (Free)
  • Download ($4.00)
  • Subscribe ($19.50)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
The Ecological Relationship of the Salamander Ambystoma laterale to its All-Female, Gynogenetic Associate
Preview not available

Abstract

In southeastern Michigan the all-female, gynogenetic salamander Ambystoma tremblayi is associated with a bisexual, diploid form, A. laterale. A. laterale has contributed two sets of chromosomes to the triploid genome of A. tremblayi. The present gynogenetic relationship between the two forms is probably a transitory stage in an evolutionary sequence that could result in the reproductive independence of the triploid line by the evolution of a parthenogenetic or of a bisexual, tetraploid form. Extinction of either form by competitive exclusion by the other form is also a possibility. Experimental larval populations in field enclosures tested the alternative hypotheses that the two forms do not overlap at all in their ecological requirements or that they interact as ecological equals. The outcomes of the experiments were measured by the survivorship of the population, the body sizes at metamorphosis and the lengths of the larval period. The results indicated that the two forms have different ecological requirements but still interact significantly. This interaction is affected by the microhabitat and the density of the population. Diploid larvae are less adversely affected by the presence of triploid larvae than triploid larvae are to the presence of diploid larvae. The shorter larval period of the diploid larvae is advantageous in the uncertain vernal pond habitat.

Page Thumbnails

  • Thumbnail: Page 
168
    168
  • Thumbnail: Page 
169
    169
  • Thumbnail: Page 
170
    170
  • Thumbnail: Page 
171
    171
  • Thumbnail: Page 
172
    172
  • Thumbnail: Page 
173
    173
  • Thumbnail: Page 
174
    174
  • Thumbnail: Page 
175
    175
  • Thumbnail: Page 
176
    176
  • Thumbnail: Page 
177
    177
  • Thumbnail: Page 
178
    178
  • Thumbnail: Page 
179
    179