On whom did the curse fall after Adam sinned?
After Adam sinned, the curse fell not just on Adam and Eve but on the whole creation. Everything came under the curse, and with the curse came death. Nothing died in Eden before Adam sinned, but death entered through his sin.
Les explains that the curse fell not only on Adam and Eve but on the entire creation, so everything came under the curse, and with the curse came death. He holds the conviction that nothing died in the Garden of Eden until Adam sinned, because animals ate herbs, fruits, and grasses, so no life was lost to support another species. Death was an unknown entity until Adam sinned. Les even ties this to good science, mentioning the laws of thermodynamics, noting the first law says nothing is being created or destroyed. He sometimes wonders whether the whole universe is also under the curse, though he has not reached a complete conclusion.