An ant garden is a mutualistic interaction between certain species of arboreal ants and various epiphytic plants. It is a structure made in the tree

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an ...

by the ants that is filled with debris and other organic matter in which epiphytes grow. The ants benefit from this arrangement by having a stable framework on which to build their nest while the plants benefit by obtaining nutrients from the soil and from the moisture retained there.

Description

Epiphytes are common in

tropical rain forest Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatori ...

and in cloud forest. An epiphyte normally derives its moisture and nutrients from the air, rain, mist and dew. Nitrogenous matter is in short supply and the epiphytes benefit significantly from the nutrients in the ant garden. The ant garden is made from "carton", a mixture of vegetable fibres, leaf debris, refuse, glandular secretions and ant faeces. The ants use this material to build their nests among the branches of the trees, to shelter the hemipteran insects that they tend in order to feed on their honeydew, and to make the pockets of material in which the epiphytes grow. The ants harvest seeds from the epiphytic plants and deposit them in the carton material. The plants have evolved various traits to encourage ants to disperse their seeds by producing chemical attractants. Eleven unrelated epiphytes that grow in ant gardens have been found to contain

methyl salicylate Methyl salicylate (oil of wintergreen or wintergreen oil) is an organic compound with the formula C8H8O3. It is the methyl ester of salicylic acid. It is a colorless, viscous liquid with a sweet, fruity odor reminiscent of root beer, but often a ...

(oil of wintergreen) and it seems likely that this compound is an ant attractant.

Examples

Species of ant that make gardens include '' Crematogaster carinata'', '' Camponotus femoratus'' and '' Solenopsis parabioticus'', all of which are parabiotic species which routinely share their nests with unrelated species of ant. Epiphytic plants that they grow include various members of the

Araceae The Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, a spathe (or leaf-like bract). A ...

, Bromeliaceae,

Cactaceae A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Gree ...

Gesneriaceae Gesneriaceae, the gesneriad family, is a family of flowering plants consisting of about 152 genera and ca. 3,540 species in the tropics and subtropics of the Old World (almost all Didymocarpoideae) and the New World (most Gesnerioideae), wi ...

Moraceae The Moraceae — often called the mulberry family or fig family — are a family of flowering plants comprising about 38 genera and over 1100 species. Most are widespread in tropical and subtropical regions, less so in temperate climates; however ...

Piperaceae The Piperaceae (), also known as the pepper family, are a large family of flowering plants. The group contains roughly 3,600 currently accepted species in 5 genera. The vast majority of species can be found within the two main genera: ''Piper'' ...

and Solanaceae. Epiphytic plants in the genus ''

Codonanthopsis ''Codonanthopsis'' is a genus of flowering plants in the family Gesneriaceae. Its native range is from southern Mexico through tropical America to Bolivia and most of Brazil. ''Codonanthopsis'' species are generally trailing epiphytes with pal ...

'', including those formerly placed in ''

Codonanthe ''Codonanthe'' is a genus of mainly epiphytic plants in the family Gesneriaceae, endemic to the Atlantic Forest of Brazil. The botanical name comes from the Ancient Greek for 'bellflower'. They have white or pale pink flowers and somewhat flesh ...

'', grow almost exclusively in ant gardens, often associated with ants of the genus '' Azteca''. The ant '' Camponotus irritabilis'' not only plants the seeds of '' Hoya elliptica'' in planned locations on its carton nest but also prunes the roots to accommodate its nest chambers and fertilises the areas where it wants extra plant growth to occur.

References

{{Reflist, refs= {{Citation , mode=cs1 , last1=Chautems , first1=Alain , last2=Perret , first2=Mathieu , date=2013 , title=Redefinition of the Neotropical Genera ''Codonanthe'' (Mart.) Hanst. and ''Codonanthopsis'' Mansf. (Gesneriaceae) , journal=Selbyana , volume=31 , issue=2 , pages=143–156 , url=https://gesneriads.info/wp-content/uploads/2019/03/Chautems-2013-codonanthe-codonanthopsis.pdf , access-date=2021-04-05 , name-list-style=amp Ants Horticulture Mutualism (biology) Myrmecology Insect behavior