User blog comment:Kogath/Monster Hunter 4 Ultimate for the Nintendo 3DS/@comment-6050823-20150522034248/@comment-5043481-20150523150824

I can't imagine tigrex being a very good forest dweller. He's really wide as it is, he would have to break down paths to move through.

Could it be that the arrival of the Nargacuga forced the primitive Tigrex Species out of the forest, being better equipped to live in the dense undergrowth?