Can a primate cross with a pig to produce viable offspring? Many scientists would say no. And yet, truth to tell, ostensible hybrids of this type, in particular ones which seem to involve human beings, have been repeatedly reported. There are dozens of newspaper reports about pig-human hybrids on record, and many additional accounts in the older literature, as well. The reports vary somewhat, but basically, they all describe creatures with the body of an ordinary pig, except for the presence of hands and/or a human-like head, that is, the front end is similar to human, the rear end, to pig.
The reports differ with respect to the claimed degree of resemblance of the foreparts to those of humans. Some, however, do allege an exact similarity (see the transcripts of old newspaper reports). The most recent accounts of ostensible pig-human hybrids (for which photographic evidence is available) depict creatures with faces that are reminiscent of, but certainly not identical to, those of human beings. Indeed, several of these recent probable hybrids have a fleshy process like an elephant trunk attached to their foreheads, a structure known as a frontal proboscis. Frontal proboscides are also mentioned in some of the older reports.
imageStrange “piglet” born in China in 2008. Note the presence of what appears to be an undetached frontal proboscis.
By those who choose to deny the possibility of distant hybridization, the condition shown here is often described as holoprosencephaly, a term used to refer to various malformations of the brain and face. In humans, the symptoms range from mild (e.g., anosomia or the presence of a single central incisor without other facial defect) to severe, for example, convergent eyes (or even cyclopia), absence of a nose, and/or the presence of a frontal proboscis (a tubular appendage attached to the forehead). Holoprosencephaly is a rare condition and its causes are not understood. The etiology is, in general, specified only vaguely as the result of a “disruption” in development. To the student of hybridization, the question of interest here is whether the disruption in such cases might be due to the incompatibility of genomes forced into interaction by the mating of two highly disparate types of organisms.