Using the biological species concept as your guide, sort the following observations based on whether they support the notion that the Big Bird lineage is a separate species or whether they refute the notion that it is a separate species.

Supports separate species: Big Bird males hold territories in and around territories of other species but breed only with Big Bird females. Big Birds have their own unique call. There is no gene flow in or out of the Big Bird populationRefutes

Separate Species: big bird can vreed with G fortis females

According to the biological concept of species, this statement confirms that the Big Bird lineage is a separate species.

Explanation:

The biological species concept states that species are groups of organisms capable of interbreeding and producing fertile offspring. Ernst Mayr (1970) literally stated that "species are groups of interbreeding natural populations that are reproductively isolated from other such groups". This statement is consistent with the lack of gene flow and reproductive isolation. In consequence, the biological concept of species is supported by above described, i. e., Big Bird males breed only with Big Bird females.

You can read this book:

Mayr, E. (1970). Populations, species, and evolution: an abridgment of animal species and evolution (Vol. 19). Editorial: Harvard University Press.