What characteristic was specifically noted about the first-generation (F1) hybrids resulting from the Père David's deer imes Red deer cross?

Answer

They were fertile

Research into the F1 progeny revealed that these first-generation hybrids were both viable and, importantly, fertile, meaning they could themselves reproduce.

What characteristic was specifically noted about the first-generation (F1) hybrids resulting from the Père David's deer 	imes Red deer cross?
speciesanimaldeerhybrid