Folivore

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Elephants are an example of a mammalian folivore. Elephant mother.jpg
Elephants are an example of a mammalian folivore.

In zoology, a folivore is a herbivore that specializes in eating leaves. Mature leaves contain a high proportion of hard-to-digest cellulose, less energy than other types of foods, and often toxic compounds. [1] For this reason, folivorous animals tend to have long digestive tracts and slow metabolisms. Many enlist the help of symbiotic bacteria to release the nutrients in their diet. Additionally, as has been observed in folivorous primates, they exhibit a strong preference for immature leaves which tend to be easier to masticate, are higher in energy and protein, and lower in fibre and poisons than more mature fibrous leaves. [1]

Contents

Folivory and flight

A hoatzin Opisthocomus hoazin.jpg
A hoatzin

It has been observed that folivory is extremely rare among flying vertebrates. [2] Morton (1978) attributed this to the fact that leaves are heavy, slow to digest, and contain little energy relative to other foods. [2] The hoatzin is an example of a flighted, folivorous bird. There are, however, many species of folivorous flying insects.

Some bats are partially folivorous; their method of deriving nourishment from leaves, according to Lowry (1989), is to chew up the leaves, swallowing the sap and spitting out the remainder. [3]

Arboreal folivores

A brown-throated three-toed sloth Bradypus.jpg
A brown-throated three-toed sloth

Arboreal mammalian folivores, such as sloths, koalas, and some species of monkeys and lemurs, tend to be large and climb cautiously. [4] Similarities in body shape and head- and tooth-structure between early hominoids and various families of arboreal folivores have been advanced as evidence that early hominoids were also folivorous. [4]

Primates

Standard ecological theory predicts relatively large group sizes for folivorous primates, as large groups offer better collective defense against predators and they face little competition for food among each other. It has been observed that these animals nevertheless frequently live in small groups. Explanations offered for this apparent paradox include social factors such as increased incidence of infanticide in large groups. [5]

A howler monkey Alouatta-caraya ppia-m01b.jpg
A howler monkey

Folivorous primates are relatively rare in the New World, the primary exception being howler monkeys. One explanation that has been offered is that fruiting and leafing occur simultaneously among New World plants. However a 2001 study found no evidence for simultaneous fruiting and leafing at most sites, apparently disproving this hypothesis. [6]

Examples

Examples of folivorous animals include:

An okapi Okapi2.jpg
An okapi

See also

Related Research Articles

<span class="mw-page-title-main">Primate</span> Order of mammals

Primates is an order of mammals, which is further divided into the strepsirrhines, which include lemurs, galagos, and lorisids; and the haplorhines, which include tarsiers; and the simians, which include monkeys and apes. Primates arose 85–55 million years ago first from small terrestrial mammals, which adapted for life in tropical forests: many primate characteristics represent adaptations to the challenging environment among tree tops, including large brain sizes, binocular vision, color vision, vocalizations, shoulder girdles allowing a large degree of movement in the upper limbs, and opposable thumbs that enable better grasping and dexterity. Primates range in size from Madame Berthe's mouse lemur, which weighs 30 g (1 oz), to the eastern gorilla, weighing over 200 kg (440 lb). There are 376–524 species of living primates, depending on which classification is used. New primate species continue to be discovered: over 25 species were described in the 2000s, 36 in the 2010s, and six in the 2020s.

<span class="mw-page-title-main">Hoatzin</span> Species of bird in South America

The hoatzin or hoactzin is a species of tropical bird found in swamps, riparian forests, and mangroves of the Amazon and the Orinoco basins in South America. It is the only extant species in the genus Opisthocomus which is the only extant genus in the Opisthocomidae family under the order of Opisthocomiformes. Despite being the subject of intense debate by specialists, the taxonomic position of this family is still far from clear.

<span class="mw-page-title-main">Howler monkey</span> Genus of mammals

Howler monkeys are the most widespread primate genus in the Neotropics and are among the largest of the platyrrhines along with the muriquis (Brachyteles), the spider monkeys (Ateles) and woolly monkeys (Lagotrix). The monkeys are native to South and Central American forests. They are famous for their loud howls, which can be heard up to three miles away through dense rain forest. Fifteen species are recognized. Previously classified in the family Cebidae, they are now placed in the family Atelidae. They are primarily folivores but also significant frugivores, acting as seed dispersal agents through their digestive system and their locomotion. Threats include human predation, habitat destruction, illegal wildlife trade, and capture for pets or zoo animals.

<span class="mw-page-title-main">Prehensile tail</span> Tail of an animal that has adapted to be able to grasp or hold objects

A prehensile tail is the tail of an animal that has adapted to grasp or hold objects. Fully prehensile tails can be used to hold and manipulate objects, and in particular to aid arboreal creatures in finding and eating food in the trees. If the tail cannot be used for this it is considered only partially prehensile; such tails are often used to anchor an animal's body to dangle from a branch, or as an aid for climbing. The term prehensile means "able to grasp".

<span class="mw-page-title-main">Colobinae</span> Subfamily of Old World monkeys

The Colobinae or leaf-eating monkeys are a subfamily of the Old World monkey family that includes 61 species in 11 genera, including the black-and-white colobus, the large-nosed proboscis monkey, and the gray langurs. Some classifications split the colobine monkeys into two tribes, while others split them into three groups. Both classifications put the three African genera Colobus, Piliocolobus, and Procolobus in one group; these genera are distinct in that they have stub thumbs. The various Asian genera are placed into another one or two groups. Analysis of mtDNA confirms the Asian species form two distinct groups, one of langurs and the other of the "odd-nosed" species, but are inconsistent as to the relationships of the gray langurs; some studies suggest that the gray langurs are not closely related to either of these groups, while others place them firmly within the langur group.

<span class="mw-page-title-main">Atelinae</span> Subfamily of New World monkeys

The Atelinae are a subfamily of New World monkeys in the family Atelidae, and includes the various spider and woolly monkeys. The primary distinguishing feature of the atelines is their long prehensile tails, which can support their entire body weight.

A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources. A specialist species can thrive only in a narrow range of environmental conditions or has a limited diet. Most organisms do not all fit neatly into either group, however. Some species are highly specialized, others less so, and some can tolerate many different environments. In other words, there is a continuum from highly specialized to broadly generalist species.

<span class="mw-page-title-main">Colombian red howler</span> Species of monkey

The Colombian red howler or Venezuelan red howler is a South American species of howler monkey, a type of New World monkey, found in the western Amazon Basin in Venezuela, Colombia, Ecuador, Peru and Brazil. The population in the Santa Cruz Department in Bolivia was split off as a separate species, the Bolivian red howler, in 1986, and more recently, splitting off the population in northeastern South America and Trinidad as the Guyanan red howler has occurred. All howler monkeys belong to the family Atelidae and the infraorder Platyrrhini.

<span class="mw-page-title-main">Brown howler</span> Species of New World monkey

The brown howler, also known as brown howler monkey, is a species of howler monkey, a type of New World monkey that lives in forests in south-eastern Brazil and far north-eastern Argentina (Misiones). It lives in groups of two to 11 individuals. Despite the name "brown howler", it is notably variable in colour, with some individuals appearing largely reddish-orange or black.

<span class="mw-page-title-main">Central American squirrel monkey</span> Species of New World monkey

The Central American squirrel monkey, also known as the red-backed squirrel monkey, is a squirrel monkey species from the Pacific coast of Costa Rica and Panama. It is restricted to the northwestern tip of Panama near the border with Costa Rica, and the central and southern Pacific coast of Costa Rica, primarily in Manuel Antonio and Corcovado National Parks.

<span class="mw-page-title-main">Mantled howler</span> Species of New World monkey

The mantled howler is a species of howler monkey, a type of New World monkey, from Central and South America. It is one of the monkey species most often seen and heard in the wild in Central America. It takes its "mantled" name from the long guard hairs on its sides.

<span class="mw-page-title-main">Yucatán black howler</span> Species of New World monkey

The Yucatán black howler, or Guatemalan black howler, is a species of howler monkey, a type of New World monkey, from Central America. It is found in Belize, Guatemala and Mexico, in and near the Yucatán Peninsula. It lives in evergreen, semideciduous and lowland rain forests. It is also known as the baboon in Belize, although it is not closely related to the baboons in Africa.

<span class="mw-page-title-main">Phayre's leaf monkey</span> Species of Old World monkey

Phayre's leaf monkey, also known as Phayre's langur, is a species of Old World monkey native to South Asia and Southeast Asia, namely India, Bangladesh, and Myanmar. Populations from further east are now thought to belong to other species. It is listed as Endangered on the IUCN Red List and is threatened by hunting and loss of habitat. The species epithet commemorates Arthur Purves Phayre.

<span class="mw-page-title-main">Dusky leaf monkey</span> Species of Old World monkey

The dusky leaf monkey, also known as the spectacled langur or the spectacled leaf monkey, is a species of primate in the family Cercopithecidae. It is found in Peninsular Malaysia, Myanmar and Thailand, and can occasionally be found in Singapore. During the day, these small, folivorous primates divide in sub-groups and forage for vegetation and fruit throughout the tropical forests. According to the IUCN, the dusky leaf monkey's population is declining due to habitat loss, poaching, and anthropogenic land use, which prompted the IUCN to classify the species as endangered in 2015.

<span class="mw-page-title-main">Mexican howler</span> Subspecies of New World monkey

The Mexican howler is a subspecies of the mantled howler, A. palliata. This subspecies is found predominantly in forests between south eastern Mexico and north eastern Peru. Typical of its species, the Mexican howler monkey has a prehensile tail, a deep jaw, and a large pharynx which it uses to make characteristically deep and resonating howls. Mantled howler monkeys are known for forming unusually large cohorts averaging 14 members and sometimes extending to 40 members.

<span class="mw-page-title-main">Tufted gray langur</span> Species of Old World monkey

The tufted gray langur, also known as Madras gray langur, and Coromandel sacred langur, is an Old World monkey, one of the species of langurs. This, like other gray langurs, is mainly a leaf-eating monkey. It is found in southeast India and Sri Lanka. It is one of three Semnopithecus species named after characters from The Iliad, S. hector and S. ajax being the others. In Sinhala it is known as හැලි වදුරා.

<i>Mesopropithecus</i> Extinct genus of small to medium-sized lemur from Madagascar

Mesopropithecus is an extinct genus of small to medium-sized lemur, or strepsirrhine primate, from Madagascar that includes three species, M. dolichobrachion, M. globiceps, and M. pithecoides. Together with Palaeopropithecus, Archaeoindris, and Babakotia, it is part of the sloth lemur family (Palaeopropithecidae). Once thought to be an indriid because its skull is similar to that of living sifakas, a recently discovered postcranial skeleton shows Mesopropithecus had longer forelimbs than hindlimbs—a distinctive trait shared by sloth lemurs but not by indriids. However, as it had the shortest forelimbs of all sloth lemurs, it is thought that Mesopropithecus was more quadrupedal and did not use suspension as much as the other sloth lemurs.

<span class="mw-page-title-main">Subfossil lemur</span> Lemurs from Madagascar that are represented by recent (subfossil) remains

Subfossil lemurs are lemurs from Madagascar that are represented by recent (subfossil) remains dating from nearly 26,000 years ago to approximately 560 years ago. They include both extant and extinct species, although the term more frequently refers to the extinct giant lemurs. The diversity of subfossil lemur communities was greater than that of present-day lemur communities, ranging to as high as 20 or more species per location, compared with 10 to 12 species today. Extinct species are estimated to have ranged in size from slightly over 10 kg (22 lb) to roughly 160 kg (350 lb). Even the subfossil remains of living species are larger and more robust than the skeletal remains of modern specimens. The subfossil sites found around most of the island demonstrate that most giant lemurs had wide distributions and that ranges of living species have contracted significantly since the arrival of humans.

<i>Anapithecus</i> Extinct genus of primates

Anapithecus is a late Miocene primate known from fossil locations in Hungary and Austria. Many Anapithecus fossils come from the site of Rudabánya, in northern Hungary, where Anapithecus lived alongside the ape Rudapithecus. The only species in the genus, Anapithecus hernyaki, is named after Gabor Hernyák, chief geologist of the Iron Ore Works of Rudabánya.

Sivaladapis is a genus of adapiform primate that lived in Asia during the middle Miocene.

References

  1. 1 2 Jones, S., Martin, R., & Pilbeam, D. (1994) The Cambridge Encyclopedia of Human Evolution. Cambridge: Cambridge University Press
  2. 1 2 Dudley, R.; Vermeij, G. J. (1992). "Do the Power Requirements of Flapping Flight Constrain Folivory in Flying Animals?". Functional Ecology. 6 (1): 101–104. JSTOR   2389776.
  3. Kunz, T. H.; Ingalls, K. A. (1994). "Folivory in Bats: An Adaptation Derived from Frugivory". Functional Ecology. 8 (5): 665–668. JSTOR   2389930.
  4. 1 2 Sarmiento, E. E. (1995). "Cautious climbing and folivory: A model of hominoid differentation". Human Evolution. 10 (4): 289–321. doi:10.1007/BF02438967.
  5. Steenbeek, R.; van Schaik, Carel P. (2001). "Competition and group size in Thomas's langurs ( Presbytis thomasi ): The folivore paradox revisited". Behavioral Ecology and Sociobiology. 49 (2–3): 100–110. doi:10.1007/s002650000286.
  6. Heymann, Eckhard W. (2001). "Can phenology explain the scarcity of folivory in New World primates?". American Journal of Primatology. 55 (3): 171–175. doi:10.1002/ajp.1050. ISSN   1098-2345. PMID   11746280. S2CID   8344876.
  7. "The Diet of a Generalized Folivore: Iguana iguana in Panama". www.anapsid.org. Retrieved 2024-02-05.