April 17, 2016 | by Michael Goulet
Our wonderful time on the islands of St. Kitts and Nevis have come to an end. While our research uncovered unfortunate information for the local officials and ecologists of St. Kitts, we believe that it is better for them to know. Now that we have shown that the two squirrels are indeed different species, new methods of intervention can be attempted.
April 17, 2016 | by Michael Goulet
Local geologists on St. Kitts and Nevis determined that at one point millions of years ago there was a land bridge between the two islands. This means the St. Kitts rodent and the Nevis rodent were once part of the same population. The population was later separated with the collapse of the land bridge that connected St. Kitts and Nevis. A portion of the population of rodents was isolated to each island. The separated portions of the original population each adapted to the island they were isolated on. This event led to the allopatric speciation of the St. Kitts and Nevis rodents.
April 13, 2016 | by Michael Goulet
The Nevis rodent has a shorter hind limb than the St. Kitts rodent which would make it jump lower than the St. Kitts rodent.This may keep the Nevis rodent from reaching certain foods. The Nevis rodent moves a lot slower which may keep it from climbing very high on a tree. This would also keep it from evading predators on land.
April 12, 2016 | by Michael Goulet
We believe that the St. Kitts rodent, thanks to natural selection and several different series of mutations, were able become superior tree climbers. Our belief is that some sort of directional selection was occuring, where rodents with longer limbs were able to more easily escape predators. As a result, the average limb length of the St. Kitts population began to increase in comparison to the Nevis population.
April 12, 2016 | by Michael Goulet
Another prezygotic reproductive barrier was determined when observing the behavior for each of the populations during courtship. Both populations have a slightly different ritual. The individuals from the Nevis population often have a longer courtship ritual, which deters most of the St. Kitts individuals from mating with them.
April 12, 2016 | by Michael Goulet
Reduced Viability in Offspring:
Prior to the Nevis population being moved to St.Kitts, the two separate populations did not have a chance to breed. Their habitats were entirely separate, which previously indicated a type of prezygotic reproductive isolation.
April 12, 2016 | by Michael Goulet
Unfortunate news! As much fun as we have been having here on St. Kitts, the same cannot be said for the island's local squirrel population. Before we arrived, the Department of Nature and Island Resources began a program involving the use of squirrels from St. Kitts' sister island, Nevis.The decision has been made to halt the project. . .for now.
April 12, 2016 | by Michael Goulet
Once again, the team here at the Island Research Institute is on the move! The Department of Nature and Island Resources of the West Indes has reached out to us for aid in saving a declining population of rodent species on the island of St. Kitts. Our team is familiar with all kinds of island dwelling creatures, but this will be our first focused study of a native rodent population.