Comparative Features of the Life Histories of Ambystoma gracile (Baird) from Populations at Low and High Altitudes
Snyder RC. 1956. Comparative Features of the Life Histories of Ambystoma gracile (Baird) from Populations at Low and High Altitudes. Copeia. 1956(1):41-50
Observations of the life cycle with regard to metamorphic behavior, the effect of altitude on neoteny, and larval breeding. Includes references to sites at Mount Rainier National Park: Tipsoo Lake, Frog Heaven, and Ricksecker Pt. ponds. The early events of the breeding period of Ambystoma gracile living at sea level are described. The length of the breeding period is about 5 1/2 weeks. A high percentage of larvae transform into subadults at one year of age; most of the remainder transform at 2 years of age. A small number evidently do not transform and remain as neotenic larvae. Neoteny and paedogenesis are described together with the appearance of the egg masses deposited by larvae. Sexual maturity is attained by larvae during the second year. The secondary sexual characteristics are described. Features of the larval life history at high elevations are compared with those at sea level. Metamorphosis appears to be uncommon in montane populations. Observations on spontaneous and thyroxin-induced metamorphosis are presented and possible interpretations of metamorphic failure at both low and high altitudes are discussed.
- Type
- Journal Article
- Authors
- Snyder, Richard
- Units
- MORA
- Keywords
- Altitude, Ambystoma decorticatum, Ambystoma maculatum, Ambystoma tigrinum, Animal Studies, Biology, Breeding, Elevation, Frog Heaven Mount Rainier National Park WA, Herpetology (Amphibians/Reptiles), Hynobius lichenatus, Lousie Lake, Mount Rainier, northwestern salamander (Abystoma gracile), Rana aurora, Rana pipiens, Reflection Lake, Ricksecker Point, Ricksecker Pt. Pond Mount Rainier National Park WA, Taricha granulosa, Tipsoo Lake Mount Rainier National Park WA, Weiss Pond