In a class taught at the University of San Diego, a professor used a slide that referred to the human fetus as a "legitimate parasite" that "invades" its mother and "manipulates" her immunity.
As Fox News reported, the lecture, reportedly part of the UC San Diego School of Medicine course, Evolution of Human Disease, "explores the major epidemiological transitions from ape-like ancestors to foraging tribes, farmers and pastoralists, to the global metropolitan primate we now are. We focus on how diseases have shaped humans and how humans have shaped disease over time."
The screenshot of the slide was sent to Dylan Griswold, a medical student at Stanford University, who tweeted it out:
The professor who allegedly showed the slide reportedly emailed the class an explanation: "Most of you probably realize that my point was to show that mammals are especially prone to invasive cancers because mammals evolved invasive placentation. My point was not to indoctrinate you with the notion that fetuses are cancers, as insinuated in the article."
Griswold pointed out the difference between a parasite and a fetus in a series of tweets, explaining:
“A baby in the womb is a parasite by definition." False: A baby in the womb is homospecific. The baby is the same species as the mother, whose body is specifically geared to gestate a baby of her own species while it lives inside her. The same cannot be said of a tapeworm. A parasite is an invading organism — coming to parasitize the host from an outside source. A fetus is formed from a fertilized egg —the egg coming from an inside source, being formed in the ovary of the mother from where it moves into the oviduct where it may be fertilized. The host-parasite relationship is one of conflict, while the mother-baby relationship is intrinsically cooperative.
Consider the immunology of the two. Host and parasite are locked in an arms race: the parasite evolves ever more complex techniques of avoidance, while the host evolves ever more complex techniques of detection and attack. Meanwhile, mother and baby cooperate to prevent immunological conflict. The site of this cooperation is the placenta. The fetus cannot be viewed as a tumor robbing the mother of nutrients. Ironically, if the mother’s health is compromised, the placenta restricts nutrient flow to the fetus to ensure the mother’s long-term health, with the prospects that the fetus can still grow and develop. Instead of being passive tissue that absorbs available nutrients from the mother, the placenta dynamically distributes nutrients between mother and fetus, optimally ensuring the health of both mother and developing baby.
Lila Rose, founder of the pro-life group Live action, tweeted, “Amid scrutiny, @UCSanDiego professor says he didn’t intend to say that “fetuses are cancers.” How about backtracking the term “parasite”? These are medically inaccurate & offensive terms, ones that abortion advocates have used for dozens of years to dehumanize children.”
The University of San Diego released a statement saying the point of the slide was to show "mammals are especially prone to invasive cancers, in part because mammals evolved the ability to host fetuses and placentas … The slide presents common, widely accepted scientific concepts and in no way represents a political statement.”