Salamanders Are Going It Alone

A paper published in the Journal of Zoology have found an unlikely way of reproducing for salamanders – where women are the only gender cloning themselves over and over again.

As Biology students will be aware, asexual reproduction via cloning is an effective way to create large numbers of one species in a short amount of time, but does not bode well for the long-term prospects of a species.

Robert Denton, the co-author of the paper, sums this problem up by saying that “if you don’t have sex, you don’t stick around very long over millions of year because you don’t get the genetic variation”, which helps species to survive as some members will be susceptible to some diseases or climatic changes, while others will not, ensuring the survival of some rather than an entire extinction.

The species of salamander is the ambystoma salamander, which resides in North American from Ohio to Quebec. However, their method of reproduction isn’t simple asexual, single-gendered reproduction, but involves the ‘theft’ of male gametes to reproduce. The reproductive strategy is known as ‘kleptogenesis’, whereby male salamanders deposit sperm packets which female salamanders pick up and use to lay eggs.

Denton goes on to say that “these animals are such an exception to the rule for how we understand vertebrate reproduction, so every piece to the puzzle is interesting.” Human Sciences applicants should consider this story in the light of human evolution, and think on how sexual reproduction and sexual dimorphism aided the evolution of the modern human.