User:Eohanlon/Spectral tarsier

• Naming/ etymology
• Taxonomy and evolution
  • "Tarsiers were once thought to be of the Strepsirrhini suborder, grouped with Lemuroidea and Lorisidae because of their similar appearance and because they have a small stature and are also nocturnal. It has been decided that tarsiers are members of the suborder haplorrhine, which is a suborder of primates that hosts tarsiers and the simians." (animal diveristy) According to Gursky et al. 2013, based on phylogenic research, tarsiers are more closely related to humans and apes then lemurs and lorises. Some scholarly articles suggest dividing the genus into 3 and some references reflect this attempted revised taxonomy. "This taxonomic discrepancy is strongly supported by data collection of physiological attributes such as coat colors, tail lengths, and size as well as molecular data(Gursky et al. 2013)." (Gursky, behavioral ecology)
  • There are 3 clades of living Tarsius species; western tarsiers, Philipine tarsiers, and Sulawesi tarsiers. These clades are composed evolutionary and geographically, as some species are found on certain islands or in particular regions (animaldiversity.org)
• Physical characteristics
  • The spectral tarsier has a body weight of 200 grams, with a body length of 240 mm, a head body length of 80 mm, and a tail length of 160 mm. Individuals are known to live for 144 months (9.5 years). When considered to include Tarsius fuscus, females of the species weigh between 102 and 114 grams (3.6 and 4.0 oz) while males are 118 to 130 grams (4.2 to 4.6 oz). It has a head-body length of 9.5 to 14 centimetres (3.7 to 5.5 in) and its tail length ranges from 20 to 26 centimetres (7.9 to 10.2 in).
• Lifespan
  • The average lifespan in the wild is thought to be 10 years; however, in captivity the closely related Horsfield's tarsier can live up to 17 years and it is thought the spectral tarsier may have similar longevity. It is believed that old age begins affecting tarsiers behavior at between 14 and 16 years of age, and apparently, like us, their hair begins to turn gray.(animaldiveristy.org)
• Distribution and habitat
  • Tarsiers inhabit the tropical forests and islands of Southeast Asia, but, according to the research done by Sabrina Archuleta with the University of Michigan's Museum of Zoology, eocene and Miocene tariser fossils have been found in China, Thailand, and southern Pakistan. The islands of Southeast Asia are actually an archipelago, which is a cluster or collection of islands. The tarsiers are found in forests that range in density and agriculture from island to island, including both primary and secondary habitats. "They roost in dense vegetation, shrubs, bamboo, palm, dense thickets of grass, bush, thorn scrubs, and secondary habitats on plantations for logging and growing coffee, nutmet, coconut, or coca crops (Archuleta, S. 2019)" (animaldiversity)
• food and foraging
  • In a study done by John and Kathy MacKinnon, it was found that tarsiers consume a completely carnivorous diet. Although some species will prey on small birds and rodents, their diet consists mainly of insects that they collect from the ground, air, and on tree branches and leaves (Mackinnon et al., 1980).
• behavior
  • Tarsiers are nocturnal mammals that awake around sunset and spend the nights foraging for insects, eating, traveling between trees, resting, and socializing. Socialization includes grooming each other,scent marking, vocalizing, and playing (Gursky 1998)
    • social structure
      • Group size is defined as the number of individuals sharing a sleeping site, and usually varies by 2 to 6 individuals (Gursky, conserv status).
      • Group composition varies from 1 adult of each sex to 1 adult male and 2 adult females and their offspring (Gursky, conserv staus).
      • In a study published in 1998, 14% of groups in the Tangkoko Dua Saudara Nature Reserve contained more than 1 adult female. In one of the groups with two adult females, both females gave birth to infants (Gursky, conserv status).
      • Males travel longer distances and occupy a larger area, while females hunt more efficiently and consume more insects.
    • reproduction and parenting
      • In a study done in North Sulawesi, Indonesia in 2007, the Mackinnons found that the spectral tarsiers were monogamous and territorial. Families regularly slept at the same sites each day and gave loud duet songs as they congregated at sleeping sites each dawn (mackinnon).
      • Tarsier young are very advanced and may travel independently as little as 23 days after birth (Mackinnon).
        • Tarsiers are both monogamous and polygynous. Some live in pairs, groups of variable size, and some males may live alone. (animaldiversity.org.)
      • Principle courtship behaviours are scent marking and genital marking for females and genital inspection for males. Copulations last between 3 and 4 minutes and for the duration of a 9 month survey (Hidayatik et al. 2018) copulation only occurred once for each pair. (HIdayatik)
      • In a northern Sulawesi rain forest, a field study was done that found that infants were alone 40%-50% of the time. Two subadults were more frequently in proximity to the infant than the adult males, the nonmaternal adult females, or the mothers were. This pattern of the subadults maintaining proximity to the infant continued when the mothers were absent. These results suggest that subadults may be guarding or babysitting infants. It is also possible that subadults are not traveling as far from the sleeping site as adults do and are therefore more likely to be found in association with the infant. (Gursky, infant care)
    • competition
      • Tarsiers regularly scent marked their ranges by rubbing branches with urine and special epigastric glands (Mackinnon).
      • The primary predators of tarsiers are monitor lizards, civets, snakes, and diverse birds of prey (animaldiversity.org).
      • Tarsier niches are largely as predator and prey. Their presence affects the population size of organism that they feed on and of those who feed on them. They are host to many different endo- and ectoparasites, including mites and intestinal worms (animaldiveristy.org)
    • communication
      • The spectral tarsier uses ultrasonic vocalizations which are of high frequency and can only travel short distances. This is called echolocation and it is used for navigation. (Gursky, echolocation).
        • 5 main categories: chirps, twitters, choruses, doubles and whistles. Chirps, twitters, and choruses extended from the audible to the ultrasonic range, the doubles and whistles were pure ultrasound. (gursky, ultrasonic vocalizations)
      • Vocalizations include high pitched whistles and chattering melodies referred to as duets. High pitched whistles are varied from simple calls to predator warnings. Some tarsiers have distinct vocalizations to mob, or ward off, a predator. (animaldiversity.org)
      • In the presence of bird predators, individuals vocalize and disperse to hide. When in the presence of a terrestrial predator, such as a snake, individuals "mob" the threat.
        • when mobbing, all individuals respond to a threat with vocalizations and each repeats lunging towards and retreating from the predator (Gursky, gregariousness)
      • The duet vocalizations are likely a mating call to lead males to females. Scent marking on trees is used to attract mates and warn off competitors by marking territory (animaldiversity.org)
• Intelligence
• poaching?
• modern conservation tactics
• in captivity
• conservation status
  • "The limited geographic distribution of this species, the lack of information on its relative abundance in other areas of its range, as well as the high rate of habitat disturbance throughout its range, suggests that the conservation status of the spectral tarsier should be changed from indeterminate to vulnerable (Gursky et al. 1998) (Conserv status).
  • Habitat loss and deforestation contributes to a decline in tarsier populations. Currently, tarisers reside in many protected areas. T. bancanus, T. dentatus, and T. tarsier are considered vulnerable. Tarsius syrichta is considered near threatened. Tarsius pelengensis and T. sangirensis are considered endangered. Tarsius tumpara is considered critically endangered. Tarsius lariang, T. pumilus, and T. wallacei are listed as data deficient. (animaldiveristy.org)