Does " make it" mean "consider the possibility that humans might be of hybrid origin"?

Context:

For example, one widespread, but erroneous, belief is that all hybrids are sterile. This idea keeps a lot of people from even considering the possibility that humans might be of hybrid origin. This assertion is absolutely false — though I have in fact heard lots of people make it. For instance, in reviewing the reports I collected for my book on hybridization in birds (http://www.oup.com/us/catalog/general/subject/LifeSciences/Ecology/~~/dmlldz11c2EmY2k9OTc4MDE5NTE4MzIzOA==, Oxford University Press, 2006), which documents some 4,000 different kinds of hybrid crosses among birds, I found that those crosses producing partially fertile hybrids are about eight times as common as crosses known to produce sterile ones. The usual result is a reduction in fertility, not absolute sterility. My current work documenting hybridization among mammals shows that partially fertile natural hybrids are common, too, in Class Mammalia. And yet, it seems most people base their ideas of hybrids on the common mule (horse x ass), which is an exceptionally sterile hybrid, and not at all representative of hybrids as a whole.