Editing Lion (section)

===Reproduction and life cycle===

{{multiple image|align=right|direction=vertical
|image1=Panthera leo massaica mating.jpg|caption1=Lions mating at Masai Mara
|image2=Lion_cub,_Masai_Mara,_Kenya.jpg|caption2=A lion cub in Masai Mara}}

Most lionesses reproduce by the time they are four years of age.<ref name="Schaller29">[[#Schaller|Schaller]], p. 29.</ref> Lions do not mate at a specific time of year and the females are [[polyestrous]].<ref name="Schaller174">[[#Schaller|Schaller]], p. 174.</ref> Like those of other cats, the male lion's penis has [[Penile spines|spines]] that point backward. During withdrawal of the penis, the spines rake the walls of the female's vagina, which may cause [[ovulation]].<ref>{{Cite journal | doi=10.1002/zoo.1430130403|title = Spontaneous and induced ovulation in the lion (Panthera leo)| journal=Zoo Biology| volume=13| issue=4| pages=301–307|year = 1994|last1 = Schramm|first1 = Ralph Dee| last2=Briggs| first2=Michael B.| last3=Reeves| first3=Jerry J.}}</ref><ref>{{Cite book |last=Asdell |first=Sydney A. |title=Patterns of mammalian reproduction |year=1993 |orig-date=1964 |publisher=Cornell University Press |location=Ithaca |isbn=978-0-8014-1753-5 |url=https://archive.org/details/asdellspatternso00hays }}</ref> A lioness may mate with more than one male when she is [[Estrous cycle|in heat]].<ref name="Schaller142">[[#Schaller|Schaller]], p. 142.</ref> Lions of both sexes may be involved in group [[Homosexuality in animals|homosexual]] and courtship activities. Males will also head-rub and roll around with each other before mounting each other.<ref>{{Cite book |last=Bagemihl |first=Bruce |year=1999 |title=Biological Exuberance: Animal Homosexuality and Natural Diversity |location=New York |publisher=St. Martin's Press |isbn=978-0-312-19239-6 |pages=[https://archive.org/details/biologicalexuber00bage/page/302 302–305] |url=https://archive.org/details/biologicalexuber00bage/page/302 }}</ref><ref>[[#Schaller|Schaller]], p. 137.</ref> [[Generation time|Generation length]] of the lion is about seven years.<ref>{{cite journal |title=Generation length for mammals |author=Pacifici, M.|author2= Santini, L.|author3= Di Marco, M.|author4= Baisero, D.|author5= Francucci, L.|author6= Grottolo Marasini, G.|author7= Visconti, P. |author8= Rondinini, C. |journal=Nature Conservation |year=2013 |issue=5 |pages=87–94}}</ref> The average gestation period is around 110{{spaces}}days;<ref name="Schaller174"/> the female gives birth to a litter of between one and four cubs in a secluded den, which may be a thicket, a reed-bed, a cave, or some other sheltered area, usually away from the pride. She will often hunt alone while the cubs are still helpless, staying relatively close to the den.<ref name="Scott45">[[#Scott|Scott]], p. 45.</ref> Lion cubs are born blind, their eyes opening around seven days after birth. They weigh {{convert|1.2|–|2.1|kg|lb|abbr=on}} at birth and are almost helpless, beginning to crawl a day or two after birth and walking around three weeks of age.<ref name="Schaller143">[[#Schaller|Schaller]], p. 143.</ref> To avoid a buildup of scent attracting the attention of predators, the lioness moves her cubs to a new den site several times a month, carrying them one-by-one by the nape of the neck.<ref name="Scott45"/>

Usually, the mother does not integrate herself and her cubs back into the pride until the cubs are six to eight weeks old.<ref name="Scott45"/> Sometimes the introduction to pride life occurs earlier, particularly if other lionesses have given birth at about the same time.<ref name=Estes/><ref name=Schaller148/> When first introduced to the rest of the pride, lion cubs lack confidence when confronted with adults other than their mother. They soon begin to immerse themselves in the pride life, however, playing among themselves or attempting to initiate play with the adults.<ref name=Schaller148/> Lionesses with cubs of their own are more likely to be tolerant of another lioness's cubs than lionesses without cubs. Male tolerance of the cubs varies—one male could patiently let the cubs play with his tail or his mane, while another may snarl and bat the cubs away.<ref>[[#Scott|Scott]], p. 46.</ref>
[[File:Lion Cubs Phinda 2011.ogv|thumb|right|Video of a lioness and her cubs in Phinda Reserve]]

Pride lionesses often synchronise their reproductive cycles and communal rearing and suckling of the young, which suckle indiscriminately from any or all of the nursing females in the pride. The synchronisation of births is advantageous because the cubs grow to being roughly the same size and have an equal chance of survival, and sucklings are not dominated by older cubs.<ref name=Estes/><ref name=Schaller148>[[#Schaller|Schaller]], p. 147-49.</ref> Weaning occurs after six or seven months. Male lions reach maturity at about three years of age and at four to five years are capable of challenging and displacing adult males associated with another pride. They begin to age and weaken at between 10 and 15 years of age at the latest.<ref>{{Cite book |last=Crandall |first=L. S. |title=The management of wild animals in captivity |year=1964 |publisher=University of Chicago Press |location=Chicago |oclc=557916}}</ref>

When one or more new males oust the previous males associated with a pride, the victors often [[infanticide (zoology)|kill any existing young cubs]], perhaps because females do not become fertile and receptive until their cubs mature or die. Females often fiercely defend their cubs from a usurping male but are rarely successful unless a group of three or four mothers within a pride join forces against the male.<ref name="Packpus83">{{Cite journal |last1=Packer |first1=C. |last2=Pusey |first2=A. E. |date=May 1983 |title= Adaptations of female lions to infanticide by incoming males|journal= American Naturalist |volume=121 |issue=5 |pages=716–728 |doi= 10.1086/284097|bibcode=1983ANat..121..716P |s2cid=84927815 }}</ref> Cubs also die from starvation and abandonment, and predation by leopards, hyenas and wild dogs. Male cubs are excluded from their maternal pride when they reach maturity at around two or three years of age,<ref name="Schaller44">[[#Schaller|Schaller]], p. 44.</ref> while some females may leave when they reach the age of two.<ref name=Packer33/> When a new male lion takes over a pride, adolescents both male and female may be evicted.<ref>[[#Scott|Scott]], p. 68.</ref>