Answer: Size
Researchers who study these sheep have most likely observed a decrease in the wild Soay's SIZE.
Wild Soay sheep live in a cold environment on a small Scottish island. The sheep used to be large because they gained extra weight during the summers in order to survive the harsh winters. A recent change in the island’s climate has caused grass to be available for a longer period each year, so survival conditions for the sheep have become less challenging.
2 answers
Technically, I don't see a question, just a statement abut sheep.