loading page

Natural selection in the origin: how does selection act on snails’ shell colour in the source of a diversified population?
  • +1
  • Shun Ito,
  • Takahiro Hirano,
  • Satoshi Chiba,
  • Junji Konuma
Shun Ito
Tohoku University
Author Profile
Takahiro Hirano
Tohoku University
Author Profile
Satoshi Chiba
Tohoku University
Author Profile
Junji Konuma
Toho University
Author Profile

Abstract

The mechanisms of adaptive radiation with phenotypic diversification and further adaptive speciation have been becoming clearer through a number of studies. Natural selection is one of the primary factors that contribute to these mechanisms. It has been demonstrated that divergent natural selection acts on a certain trait in adaptive radiation. However, it is not often known how natural selection acts on the source of a diversified population, although it has been detected in phylogenetic studies. Our study demonstrates how selection acts on a trait in a source population of diversified population using the Japanese land snail Euhadra peliomphala simodae. This snail’s shell colour has diversified due to disruptive selection after migration from the mainland to islands. We used trail-camera traps to identify the cause of natural selection on both the mainland and an island. We then conducted a mark-recapture experiment on the mainland to detect natural selection and compare the shape and strength of it to previous study in an island. In total, we captured and marked around 1,700 snails, and some of them were preyed on by an unknown predator. The trail-camera traps showed that the predator is the large Japanese field mouse Apodemus speciosus, but this predation did not correlate with shell colour. A Bayesian approach showed that the stabilising selection from factors other than predation acted on shell colour. Our results suggest that natural selection was changed by migration, which could explain the ultimate cause of phenotypic diversification in adaptive radiation that was not due to predation.

Peer review status:IN REVISION

03 Jun 2021Submitted to Ecology and Evolution
03 Jun 2021Assigned to Editor
03 Jun 2021Submission Checks Completed
06 Jun 2021Review(s) Completed, Editorial Evaluation Pending
07 Jun 2021Editorial Decision: Revise Minor