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Treeshrew

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38-760: The treeshrews (also called tree shrews or banxrings ) are small mammals native to the tropical forests of South and Southeast Asia . They make up the entire order Scandentia , which split into two families : the Tupaiidae (19 species, "ordinary" treeshrews), and the Ptilocercidae (one species, the pen-tailed treeshrew ). Though called 'treeshrews', and despite having previously been classified in Insectivora , they are not true shrews , and not all species live in trees . They are omnivores ; among other things, treeshrews eat fruit. Treeshrews have

76-464: A behavior unique among mammals other than humans. A single TRPV1 mutation reduces their pain response to capsaicinoids, which scientists believe is an evolutionary adaptation to be able to consume spicy foods in their natural habitats. Pitcher plants like the Nepenthes lowii , supplements its carnivorous diet with tree shrew droppings. They make up the entire order Scandentia , split into

114-432: A few minutes every other day to suckle them. Treeshrews reach sexual maturity after around four months, and breed for much of the year, with no clear breeding season in most species. Treeshrews live in small family groups, which defend their territory from intruders. Most are diurnal , although the pen-tailed treeshrew is nocturnal . They mark their territories using various scent glands or urine , depending on

152-411: A higher brain to body mass ratio than any other mammal, including humans , but high ratios are not uncommon for animals weighing less than 1 kg (2 lb). Among orders of mammals, treeshrews are closely related to primates , and have been used as an alternative to primates in experimental studies of myopia , psychosocial stress, and hepatitis . The name Tupaia is derived from tupai ,

190-436: A separate order ( Erinaceomorpha ) from the remainder (termed Soricomorpha ), comprising the families Soricidae ( shrews ), Talpidae ( moles ), Solenodontidae, and Nesophontidae. These two orders then replaced Insectivora. This scheme was undermined when molecular studies indicated that Soricomorpha is paraphyletic , because Soricidae shared a more recent common ancestor with Erinaceidae than with other soricomorphs. However,

228-399: Is binocular in the case of the more arboreal species. Female treeshrews have a gestation period of 45–50 days and give birth to up to three young in nests lined with dry leaves inside tree hollows. The young are born blind and hairless, but are able to leave the nest after about a month. During this period, the mother provides relatively little maternal care, visiting her young only for

266-675: Is a vertebrate animal of the class Mammalia ( / m ə ˈ m eɪ l i . ə / ). Mammals are characterized by the presence of milk -producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair , and three middle ear bones . These characteristics distinguish them from reptiles and birds , from which their ancestors diverged in the Carboniferous Period over 300 million years ago. Around 6,400 extant species of mammals have been described and divided into 27 orders . The largest orders of mammals, by number of species , are

304-529: Is a now-abandoned biological grouping within the class of mammals . Some species have now been moved out, leaving the remaining ones in the order Eulipotyphla within the larger clade Laurasiatheria , which makes up one of the basal clades of placental mammals . Before the era of widespread DNA sequencing , the grouping was used as a polyphyletic taxon for a variety of small to very small, relatively unspecialised mammals that feed upon insects. Since any primitive-looking fossil group of placental mammals

342-555: Is different enough to warrant placement in its own family, Ptilocercidae ; the two families are thought to have separated 60 million years ago. The former Tupaiidae genus Urogale was disbanded in 2011 when the Mindanao treeshrew was moved to Tupaia based on a molecular phylogeny. The fossil record of treeshrews is poor. The oldest putative treeshrew, Eodendrogale parva , is from the Middle Eocene of Henan , China, but

380-572: Is primarily driven by human poaching and habitat destruction , primarily deforestation . Over 70% of mammal species are in the orders Rodentia , Chiroptera , and Eulipotyphla . Mammal classification has been through several revisions since Carl Linnaeus initially defined the class, and at present , no classification system is universally accepted. McKenna & Bell (1997) and Wilson & Reeder (2005) provide useful recent compendiums. Simpson (1945) provides systematics of mammal origins and relationships that had been taught universally until

418-426: Is the viviparous placental mammals , so named for the temporary organ ( placenta ) used by offspring to draw nutrition from the mother during gestation . Most mammals are intelligent , with some possessing large brains, self-awareness , and tool use . Mammals can communicate and vocalize in several ways, including the production of ultrasound , scent marking , alarm signals , singing , echolocation ; and, in

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456-473: The Cretaceous . The relationships between these three lineages is contentious, and all three possible hypotheses have been proposed with respect to which group is basal . These hypotheses are Atlantogenata (basal Boreoeutheria), Epitheria (basal Xenarthra) and Exafroplacentalia (basal Afrotheria). Boreoeutheria in turn contains two major lineages— Euarchontoglires and Laurasiatheria . Estimates for

494-564: The International Union for Conservation of Nature (IUCN) completed a five-year Global Mammal Assessment for its IUCN Red List , which counted 5,488 species. According to research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495, including 96 recently extinct. The word " mammal " is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from

532-556: The Latin mamma ("teat, pap"). In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group of mammals, the clade consisting of the most recent common ancestor of living monotremes ( echidnas and platypuses ) and therian mammals ( marsupials and placentals ) and all descendants of that ancestor. Since this ancestor lived in the Jurassic period, Rowe's definition excludes all animals from

570-514: The Malay word for squirrel , and was provided by Sir Stamford Raffles . Treeshrews are slender animals with long tails and soft, greyish to reddish-brown fur. The terrestrial species tend to be larger than the arboreal forms, and to have larger claws, which they use for digging up insect prey. They have poorly developed canine teeth and unspecialised molars, with an overall dental formula of 2.1.3.3 3.1.3.3 Treeshrews have good vision , which

608-606: The biological classification scheme used, are the primates : apes , monkeys , and lemurs ; the Cetartiodactyla : whales and even-toed ungulates ; and the Carnivora which includes cats , dogs , weasels , bears , seals , and allies. According to Mammal Species of the World , 5,416 species were identified in 2006. These were grouped into 1,229  genera , 153  families and 29 orders. In 2008,

646-406: The dominant terrestrial animal group from 66 million years ago to the present. The basic mammalian body type is quadrupedal , with most mammals using four limbs for terrestrial locomotion ; but in some, the limbs are adapted for life at sea , in the air , in trees or underground . The bipeds have adapted to move using only the two lower limbs, while the rear limbs of cetaceans and

684-450: The families Tupaiidae , the treeshrews, and Ptilocercidae , the pen-tailed treeshrew. The 20  species are placed in five genera . Treeshrews were moved from the order Insectivora into the order Primates because of certain internal similarities to primates (for example, similarities in the brain anatomy , highlighted by Sir Wilfrid Le Gros Clark ), and classified as a "primitive prosimian ", however they were soon split from

722-428: The rodents , bats , and Eulipotyphla (including hedgehogs , moles and shrews ). The next three are the primates (including humans , monkeys and lemurs ), the even-toed ungulates (including pigs , camels , and whales ), and the Carnivora (including cats , dogs , and seals ). Mammals are the only living members of Synapsida ; this clade , together with Sauropsida (reptiles and birds), constitutes

760-439: The sea cows are mere internal vestiges . Mammals range in size from the 30–40 millimetres (1.2–1.6 in) bumblebee bat to the 30 metres (98 ft) blue whale —possibly the largest animal to have ever lived. Maximum lifespan varies from two years for the shrew to 211 years for the bowhead whale . All modern mammals give birth to live young, except the five species of monotremes , which lay eggs. The most species-rich group

798-796: The Euarchonta are sister to the Glires ( lagomorphs and rodents ), and the two groups are combined into the superorder Euarchontoglires . However, the alternative placement of treeshrews as sister to both Glires and Primatomorpha cannot be ruled out. Some studies place Scandentia as sister of the Glires, which would invalidate Euarchonta: It is this organization that is shown in the tree diagram below. Scandentia (treeshrews) Lagomorpha (rabbits, hares, pikas) Rodentia (rodents) Dermoptera (colugos) † Plesiadapiformes Primates Several other arrangements of these orders have been proposed in

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836-404: The Euarchonta group: Lagomorpha (rabbits, hares, pikas) Rodentia (rodents) Scandentia (treeshrews) Dermoptera (colugos) Primates († Plesiadapiformes , Strepsirrhini , Haplorrhini ) The 23  species are placed in four genera , which are divided into two families. The majority are in the "ordinary" treeshrew family, Tupaiidae , but one species, the pen-tailed treeshrew ,

874-492: The case of humans, complex language . Mammals can organize themselves into fission–fusion societies , harems , and hierarchies —but can also be solitary and territorial . Most mammals are polygynous , but some can be monogamous or polyandrous . Domestication of many types of mammals by humans played a major role in the Neolithic Revolution , and resulted in farming replacing hunting and gathering as

912-812: The clade originating with the last common ancestor of Sinoconodon and living mammals. The earliest-known synapsid satisfying Kemp's definitions is Tikitherium , dated 225 Ma , so the appearance of mammals in this broader sense can be given this Late Triassic date. However, this animal may have actually evolved during the Neogene. As of the early 21st century, molecular studies based on DNA analysis have suggested new relationships among mammal families. Most of these findings have been independently validated by retrotransposon presence/absence data . Classification systems based on molecular studies reveal three major groups or lineages of placental mammals— Afrotheria , Xenarthra and Boreoeutheria —which diverged in

950-444: The closest thing to an official classification of mammals, despite its known issues. Most mammals, including the six most species-rich orders , belong to the placental group. The three largest orders in numbers of species are Rodentia : mice , rats , porcupines , beavers , capybaras , and other gnawing mammals; Chiroptera : bats; and Eulipotyphla : shrews , moles , and solenodons . The next three biggest orders, depending on

988-473: The combination of Soricidae and Erinaceidae, referred to as order Eulipotyphla , has been shown to be monophyletic. Family-level cladogram of extant insectivoran relationships, following Roca et al.: Solenodontidae Talpidae Soricidae Erinaceidae These families have been placed within Insectivora in the past: Not to be confused with insectivores (the eaters of insects considered as

1026-1382: The divergence times between these three placental groups range from 105 to 120 million years ago, depending on the type of DNA used (such as nuclear or mitochondrial ) and varying interpretations of paleogeographic data. Monotremata Marsupialia Xenarthra Afrotheria Glires Euarchonta [REDACTED] Eulipotyphla Chiroptera Pholidota Carnivora [REDACTED] Perissodactyla [REDACTED] Artiodactyla [REDACTED] Monotremata [REDACTED] Paucituberculata [REDACTED] Didelphimorphia [REDACTED] Microbiotheria Notoryctemorphia [REDACTED] Peramelemorphia [REDACTED] Dasyuromorphia [REDACTED] Diprotodontia [REDACTED] Cingulata [REDACTED] Pilosa [REDACTED] Hyracoidea [REDACTED] Sirenia [REDACTED] Proboscidea [REDACTED] Tubulidentata [REDACTED] Macroscelidea [REDACTED] Afrosoricida [REDACTED] Eulipotyphla [REDACTED] Chiroptera [REDACTED] Pholidota [REDACTED] Carnivora [REDACTED] Perissodactyla [REDACTED] Artiodactyla [REDACTED] Scandentia [REDACTED] Lagomorpha [REDACTED] Insectivora The order Insectivora (from Latin insectum "insect" and vorare "to eat")

1064-585: The earlier Triassic , despite the fact that Triassic fossils in the Haramiyida have been referred to the Mammalia since the mid-19th century. If Mammalia is considered as the crown group, its origin can be roughly dated as the first known appearance of animals more closely related to some extant mammals than to others. Ambondro is more closely related to monotremes than to therian mammals while Amphilestes and Amphitherium are more closely related to

1102-451: The end of the 20th century. However, since 1945, a large amount of new and more detailed information has gradually been found: The paleontological record has been recalibrated, and the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself, partly through the new concept of cladistics . Though fieldwork and lab work progressively outdated Simpson's classification, it remains

1140-825: The identity of this animal is uncertain. Other fossils have come from the Miocene of Thailand, Pakistan, India, and Yunnan , China, as well as the Pliocene of India. Most belong to the family Tupaiidae; one fossil species described from the Oligocene of Yunnan is thought to be closer to the pen-tailed treeshrew. Named fossil species include Prodendrogale yunnanica , Prodendrogale engesseri , and Tupaia storchi from Yunnan, Tupaia miocenica from Thailand, Palaeotupaia sivalicus from India and Ptilocercus kylin from Yunnan. [REDACTED] Mammal A mammal (from Latin mamma  'breast')

1178-668: The larger Amniota clade. Early synapsids are referred to as " pelycosaurs ." The more advanced therapsids became dominant during the Guadalupian . Mammals originated from cynodonts , an advanced group of therapsids, during the Late Triassic to Early Jurassic . Mammals achieved their modern diversity in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of non-avian dinosaurs , and have been

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1216-563: The particular species. Treeshrews are omnivorous , feeding on insects, small vertebrates, fruit, and seeds. Among other things, treeshrews eat Rafflesia fruit. The pen-tailed treeshrew in Malaysia is able to consume large amounts of naturally fermented nectar from flower buds of the bertam palm Eugeissona tristis (with up to 3.8% alcohol content) the entire year without it having any effects on behaviour. Treeshrews have also been observed intentionally eating foods high in capsaicin ,

1254-437: The past, and the above tree is only a well-favored proposal. Although it is known that Scandentia is one of the most basal euarchontoglire clades, the exact phylogenetic position is not yet considered resolved: It may be a sister of Glires, Primatomorpha, or Dermoptera , or separate from and sister to all other Euarchontoglires. Shared short interspersed nuclear elements (SINEs) offer strong evidence for Scandentia belonging to

1292-716: The primary source of food for humans. This led to a major restructuring of human societies from nomadic to sedentary, with more co-operation among larger and larger groups, and ultimately the development of the first civilizations . Domesticated mammals provided, and continue to provide, power for transport and agriculture, as well as food ( meat and dairy products ), fur , and leather . Mammals are also hunted and raced for sport, kept as pets and working animals of various types, and are used as model organisms in science. Mammals have been depicted in art since Paleolithic times, and appear in literature, film, mythology, and religion. Decline in numbers and extinction of many mammals

1330-411: The primates and moved into their own clade . Taxonomists continue to refine the treeshrews' relations to primates and to other closely related clades. Molecular phylogenetic studies have suggested that the treeshrews should be given the same rank ( order ) as the primates and, with the primates and the flying lemurs (colugos), belong to the grandorder Euarchonta . According to this classification,

1368-548: The therians; as fossils of all three genera are dated about 167 million years ago in the Middle Jurassic , this is a reasonable estimate for the appearance of the crown group. T. S. Kemp has provided a more traditional definition: " Synapsids that possess a dentary – squamosal jaw articulation and occlusion between upper and lower molars with a transverse component to the movement" or, equivalently in Kemp's view,

1406-472: Was commonly assigned to this order for convenience, it was held to constitute the basal stock out of which other placental orders had evolved. Therefore, at its widest extent, the order Insectivora represented an evolutionary grade rather than a clade . Taxonomy has been refined in recent years, and treeshrews , elephant shrews , and colugos have now been placed in separate orders, as have many fossil groups that were formerly included here. For some time it

1444-403: Was held that the remaining insectivoran families constituted a monophyletic grouping, or clade, to which the name Lipotyphla had long been applied. However, molecular evidence indicated that Chrysochloridae ( golden moles ), Tenrecidae ( tenrecs ), and Potamogalidae ( otter shrews ) should also be separated as a new order Afrosoricida . Erinaceidae ( hedgehogs ) was then also split off into

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