''Thamnophis'' Mating balls are a brief

gregarious Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies. Sociality is a survival response to evolutionary pressures. For example, when a mother wasp ...

structure resulting from a mating behaviour wherein a large number of individuals cluster together while mating. It has been observed in various kinds of animals including

toad Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands. A distinction between frogs and toads is not made in scientif ...

s, bees and wasps, and snakes such as

garter snakes Garter snake is a common name for generally harmless, small to medium-sized snakes belonging to the genus ''Thamnophis'' in the family Colubridae. Native to North and Central America, species in the genus ''Thamnophis'' can be found from the sub ...

and

anaconda Anacondas or water boas are a group of large snakes of the genus '' Eunectes''. They are found in tropical South America. Four species are currently recognized. Description Although the name applies to a group of snakes, it is often used ...

s. Often the ball consists of a single female and many males; a particularly asymmetrical case is that of the red-sided garter snakes which form each spring some of the most populous mating balls observed, in which as many as a hundred males try to reproduce with a single female.

Herptiles

Common toad Bufo bufo multiple amplexus mating ball

poikilotherm A poikilotherm () is an animal whose internal temperature varies considerably. Poikilotherms have to survive and adapt to environmental stress. One of the most important stressors is temperature change, which can lead to alterations in membrane ...

s, reptiles and amphibians are susceptible to sluggishness from cold weather. This causes a

sexual competition Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex (i ...

among the first individuals to emerge from brumation to successfully mate before competitors are fully active. Body contact between members of the ball conserves the group's heat to enable the activity of mating to continue. Mating ball behaviour has been observed in '' Thamnophis'' species, '' Cubophis vudii'', ''

Natrix natrix The grass snake (''Natrix natrix''), sometimes called the ringed snake or water snake, is a Eurasian non-venomous colubrid snake. It is often found near water and feeds almost exclusively on amphibians. Subspecies Many subspecies are recogni ...

'', ''

Bufo bufo The common toad, European toad, or in Anglophone parts of Europe, simply the toad (''Bufo bufo'', from Latin ''bufo'' "toad"), is a frog found throughout most of Europe (with the exception of Ireland, Iceland, and some Mediterranean islands), in ...

'', '' Bufo boreas'', and other species. In the context of amphibians, mating balls are sometimes known as 'multiple

amplexus Amplexus (Latin "embrace") is a type of mating behavior exhibited by some externally fertilizing species (chiefly amphibians and horseshoe crabs) in which a male grasps a female with his front legs as part of the mating process, and at the same ...

Insects

''B. quinquespinosus'' Kevin M. O'Neill has observed mating balls in ''

Bembecinus quinquespinosus ''Bembecinus quinquespinosus'' is a species of sand wasp in the family Crabronidae. It is found in the Caribbean Sea The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Ze ...

''. ''

Habropoda miserabilis ''Habropoda'' is a genus of anthophorine bees in the family Apidae Apidae is the largest family within the superfamily Apoidea, containing at least 5700 species of bees. The family includes some of the most commonly seen bees, including bumbl ...

'' also mate in balls. The phenomenon has been observed infrequently in stoneflies, although it is thought that it may be more common than might be inferred from observations thus far.

Japanese beetle The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. The adult measures in length and in width, has iridescent copper-colored elytra and a green thorax and head. It is not very destructive in Japan (where it is controlle ...

s also make large mating balls, of which the occurrence in human spaces contributes to their being commonly regarded as a

pest species A pest is any animal or plant harmful to humans or human concerns. The term is particularly used for creatures that damage crops, livestock, and forestry or cause a nuisance to people, especially in their homes. Humans have modified the environ ...

. Once the female emerges from the ground, she releases a

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

which attracts other beetles to form the mating ball. These balls are unusual among insects in that there may be multiple females in each one.

References

category:mating systems

Herptiles

Insects

See also

References