Editing Humanzee (section)

== Possibility ==
The possibility of hybrids between humans and other [[ape]]s has been entertained since at least the medieval period; Saint [[Peter Damian]] (11th century) claimed to have been told of the offspring of a human woman who had mated with a non-human ape,<ref name="Damian">{{cite book |last=Damiani |first=Saint Petri |url=https://books.google.com/books?id=0MEUAAAAQAAJ&pg=PA789 |title=Chap. 29: ''De simia, et quo pacto simia capi possit.'' |year=1853 |editor=Constantinus Caietanus |series=Opus 52: De Bono Religiosi Status et Variarum Animantium Topologia |volume=145 |pages=789, 790 |language=la |quote=''Ait [Alexander papa] enim quia nuper comes Gulielmus in [[Liguria]]e partibus habitans marem habebat simiae, qui vulgo maimo dicitur, cum quo et uxor eius, ut erat impudica prorsus ac petulans, lascivius jocabatur. Nam et ego duos eius filios vidi, quos de episcopo quodam plectibilis lupa pepererat; ... cum femina fera concubuit; ... Enimvero nuper allatus est praefato papae, et simul et nobis grandiusculus quidam puer; et si jam, ut dicitur, vicennalis, tamen prorsus elinguis et maimoni forma consimilis, ita ut eodem vocabulo nuncupetur.'' ("For [ [[Pope Alexander II]] ] says that recently Count William who lived in the area of [[Liguria]] had a male ape, who was called maimo [?], with which also his wife, as she was exceedingly impudent and wanton, played in a more lascivious manner. For I also have seen two sons of hers which the punishable whore bore of a certain bishop. ... the beast mated with the woman; ... So then, according to the pope's account, at the same time as for us, a rather large boy was born; and although, as it is said, he is already 20 years old, he is still unable to speak and looks like the maimo, so he is called by that same name.") |author-link=Peter Damian |access-date=4 September 2019}}</ref> and so did [[Antonio Zucchelli]], an Italian Franciscan capuchin friar who was a missionary in Africa from 1698 to 1702,<ref>{{Cite web|url=https://books.google.com/books?id=PAI_AAAAcAAJ&pg=PA107|title=Relazioni del viaggio e missione di Congo nell'Etiopia inferiore occidentale|last1=Zucchelli|first1=Antonio|year=1712}}</ref> and Sir [[Edward Coke]] in "The Institutes of the Lawes of England".<ref>{{Cite web|url=https://archive.org/details/institutesoflaws00cokeuoft/page/59/mode/2up?ref=ol&view=theater|title = Institutes of the laws of England : Or a commentary upon Littleton, not the name of the author only, but of the law itself}}</ref> 

Chimpanzees and humans are closely related.<ref name="Prüfer-2012">{{Cite journal |last1=Prüfer |first1=Kay |last2=Munch |first2=Kasper |last3=Hellmann |first3=Ines |last4=Akagi |first4=Keiko |last5=Miller |first5=Jason R. |last6=Walenz |first6=Brian |last7=Koren |first7=Sergey |last8=Sutton |first8=Granger |last9=Kodira |first9=Chinnappa |last10=Winer |first10=Roger |last11=Knight |first11=James R. |last12=Mullikin |first12=James C. |last13=Meader |first13=Stephen J. |last14=Ponting |first14=Chris P. |last15=Lunter |first15=Gerton |date=June 2012 |title=The bonobo genome compared with the chimpanzee and human genomes |journal=Nature |volume=486 |issue=7404 |pages=527–531 |bibcode=2012Natur.486..527P |doi=10.1038/nature11128 |issn=1476-4687 |pmc=3498939 |pmid=22722832}}</ref> [[List of genetic hybrids|Genetic animal hybrids]] with different chromosome numbers decrease the probability of [[Genetic viability|viable]] offspring and rarely occur in the first cross.<ref name="McCarthy-2008">{{Cite book |last=McCarthy |first=Eugene |url=https://www.macroevolution.net/support-files/forms_of_life.pdf |title=On the Origin of New Forms of Life A New Theory |publisher=macroevolution.net |year=2008 |location=United States |pages=34 }}</ref> Evolutionary biologists have found evidence that hybridization between humans and [[Chimpanzee|''Pan troglodytes'']] resulted in some varieties of [[archaic humans]].<ref name="Caparros-2021">{{Cite journal |last1=Caparros |first1=Miguel |last2=Prat |first2=Sandrine |date=2021-04-23 |title=A Phylogenetic Networks perspective on reticulate human evolution |journal=iScience |volume=24 |issue=4 |pages=102359 |doi=10.1016/j.isci.2021.102359 |pmid=33898948 |pmc=8054162 |bibcode=2021iSci...24j2359C |issn=2589-0042}}</ref><ref name="Arnold-2006">{{Cite journal |last1=Arnold |first1=Michael L. |last2=Meyer |first2=Axel |date=2006 |title=Natural hybridization in primates: one evolutionary mechanism |url=https://pubmed.ncbi.nlm.nih.gov/16945512/ |journal=Zoology (Jena, Germany) |volume=109 |issue=4 |pages=261–276 |doi=10.1016/j.zool.2006.03.006 |issn=0944-2006 |pmid=16945512|bibcode=2006Zool..109..261A }}</ref><ref name="McCarthy-2008" /><ref name="Winder-2014">{{Cite journal |last1=Winder |first1=Isabelle C. |last2=Winder |first2=Nick P. |date=2014 |title=Reticulate evolution and the human past: an anthropological perspective |url=https://pubmed.ncbi.nlm.nih.gov/24932745/ |journal=Annals of Human Biology |volume=41 |issue=4 |pages=300–311 |doi=10.3109/03014460.2014.922613 |issn=1464-5033 |pmid=24932745}}</ref> Chimpanzees and [[bonobo]]s are separate species, but hybridization has been documented.<ref>{{Cite journal |last1=Vervaecke |first1=Hilde |last2=Elsacker |first2=Van |date=January 1992 |title=Hybrids between common chimpanzees (Pan troglodytes) and pygmy chimpanzees (Pan paniscus) in captivity |url=https://www.researchgate.net/publication/272356540 |journal=Mammalia |volume=56 |pages=667–669 |via=[[ResearchGate]]}}</ref> Genetic similarity, and thus the chances of successful hybridization, is not always correlated with visual appearances. Domestication and backcrossing has been found to increase fertility in subsequent generations.<ref name="McCarthy-2008"/><ref>{{Cite book |last=Darwin |first=Charles |url=https://archive.org/details/in.ernet.dli.2015.216923/page/n193/mode/2up?q=domestication |title=The Descent of Man. |year=1896}}</ref>

All [[great ape]]s have similar genetic chromosome structure. Humans have one pair fewer chromosomes than other apes, as humans have 23 chromosome pairs, while all other apes have 24,<ref>{{Cite news |last=Hugo |first=Kristin |date=2018-02-18 |title=Could Chimps and Humans Mate? Tales of 'Humanzee' Hybrid Are Murky and Likely Impossible |work=Newsweek |url=https://www.newsweek.com/could-chimp-humans-mate-tales-humanzee-hybrids-murky-likely-impossible-796646}}</ref> with ape chromosomes 12 and 13 fused in the human genome into a large chromosome (which contains remnants of the [[centromere]] and [[telomere]]s of the ancestral 12 and 13).<ref>{{cite journal |last1=Fan |first1=Yuxin |last2=Elena |first2=Linardopoulou |last3=Friedman |first3=Cynthia |last4=Williams |first4=Eleanor |last5=Trask |first5=Barbara J. |title=Genomic Structure and Evolution of the Ancestral Chromosome Fusion Site in 2q13–2q14.1 and Paralogous Regions on Other Human Chromosomes |journal=Genome Research |date=2002 |volume=12 |issue=11 |pages=1651–1662 |doi=10.1101/gr.337602 |pmid=12421751 |pmc=187548 }}</ref><ref name=pnastt>{{cite journal |vauthors=IJdo JW, Baldini A, Ward DC, Reeders ST, Wells RA |title=Origin of human chromosome 2: an ancestral telomere–telomere fusion |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=88 |issue=20 |pages=9051–5 |date=October 1991 |pmid=1924367 |pmc=52649 |doi= 10.1073/pnas.88.20.9051|bibcode=1991PNAS...88.9051I |doi-access=free }}</ref> Chromosomes 6, 13, 19, 21, 22, and X are structurally the same in all great apes. Chromosomes 3, 11, 14, 15, 18, and 20 match among [[gorilla]]s, chimpanzees, and humans. Chimpanzees and humans match on 1, 2p, 2q, 5, 7–10, 12, 16, and Y as well. Some older references include Y as a match among gorillas, chimpanzees, and humans, but chimpanzees, bonobos, and humans have recently been found to share a large transposition from chromosome 1 to Y not found in other apes.<ref name=defphc>{{cite journal |vauthors=Wimmer R, Kirsch S, Rappold GA, Schempp W |title=Direct Evidence for a Pan–Homo Clade |journal=Chromosome Research |volume=10 |issue=1 |pages=55–61 |doi=10.1023/A:1014222311431 |year=2002 |pmid=11863072|s2cid=20147726 }}</ref><ref name="Prüfer-2012" /><ref name="Caparros-2021" /><ref name="Arnold-2006" />

The degree of chromosomal similarity among apes is roughly equivalent to that found in [[Equus (genus)|equines]]. Interfertility of horses and donkeys is common, although sterility of the offspring ([[mule]]s) is more common. Complexities and partial sterility pertain to horse–zebra hybrids, or [[zorse]]s, whose chromosomal disparity is very wide, with horses typically having 32 chromosome pairs and zebras between 16 and 23 depending on species. The [[Przewalski's horse]] (''Equus ferus przewalskii'') with 33 chromosome pairs, and the domestic horse (''E. f. caballus'') with 32 pairs, have been found to be interfertile, and produce semi-fertile offspring: male hybrids can breed with female domestic horses.<ref name=ncbicyt>{{cite journal | last1 = Chandley | first1 = AC | last2 = Short | first2 = RV | last3 = Allen | first3 = WR | title = Cytogenetic studies of three equine hybrids | journal = Journal of Reproduction and Fertility | issue = 23 | pages = 356–70 | year = 1975 | pmid = 1060807 }}</ref>

In 1977, researcher J. Michael Bedford discovered that human [[sperm]] could penetrate the protective outer membranes of a [[gibbon]] egg.<ref>{{cite journal |author=Bedford JM |title=Sperm/egg interaction: the specificity of human spermatozoa |journal=Anat. Rec. |volume=188 |issue=4 |pages=477–87 |date=August 1977 |pmid=409311 |doi=10.1002/ar.1091880407 |s2cid=19052254 }}</ref> Bedford's paper also stated that human [[spermatozoa]] would not even attach to the [[zona pellucida|zona surface]] of non-[[hominoid]] primates ([[baboon]], [[rhesus monkey]], and [[squirrel monkey]]), concluding that although the specificity of human spermatozoa is not confined to ''[[Homo sapiens]] sapiens'' alone, it is probably restricted to the [[Hominoidea]]. However, in the opposite direction of closely related species, it has been found that human sperm binds to gorilla [[oocyte]]s with almost the same ease as to human ones.<ref>{{Cite journal |pmid = 1571161|year = 1992|last1 = Lanzendorf|first1 = S. E.|title = Hemizona assay for measuring zona binding in the lowland gorilla|journal = Molecular Reproduction and Development|volume = 31|issue = 4|pages = 264–7|last2 = Holmgren|first2 = W. J.|last3 = Johnson|first3 = D. E.|last4 = Scobey|first4 = M. J.|last5 = Jeyendran|first5 = R. S.|doi = 10.1002/mrd.1080310407|s2cid = 26770937}}</ref>

Hybridization between members of different, but related genera is sometimes possible, as in the case of [[Cama (animal)|cama]] (camel and llama), [[wholphin]] ([[common bottlenose dolphin]] and [[false killer whale]]), and some [[felid hybrid]]s. Even hybridization between different [[Family (biology)|families]], as in the case of the [[sturddlefish]],{{efn|A hybrid between the [[American paddlefish]] (Family: [[Paddlefish|Polyodontidae]]) and the [[Russian sturgeon]] (Family: [[Sturgeon|Acipenseridae]]), created in a [[wiktionary:freak accident|freak lab accident]] in 2019 when Hungarian scientists attempted to induce [[gynogenesis]] in female sturgeons with paddlefish sperm.}} is possible (albeit exceedingly rare) provided the parent species are genetically similar enough to one another.<ref name="sturddlefish">{{cite news|last1=Roth|first1=Annie|title=Scientists Accidentally Bred the Fish Version of a Liger|url=https://www.nytimes.com/2020/07/15/science/hybrid-sturgeon-paddlefish.html|access-date=8 April 2024|work=[[The New York Times]]|date=15 July 2020}}</ref>