The pen-tailed treeshrew (''Ptilocercus lowii'') is a treeshrew of the family Ptilocercidae native to southern

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

, the

Malay Peninsula The Malay Peninsula is located in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area contains Peninsular Malaysia, Southern Tha ...

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

, and some

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

n islands. It is the only living species in the genus ''Ptilocercus''. All other treeshrew species are grouped in the family Tupaiidae.

Distribution and habitat

The pen-tailed treeshrew occurs from southern Thailand and the Malay Peninsula to northern Sumatra, Siberut, Bangka Island and northwestern

. It inhabits foremost primary forest up to an elevation of , where undergrowth is dense.

Behaviour and ecology

Pen-tailed treeshrews studied in Malaysia spent several hours per night consuming naturally fermented

nectar Nectar is a viscous, sugar-rich liquid produced by Plant, plants in glands called nectaries, either within the flowers with which it attracts pollination, pollinating animals, or by extrafloral nectaries, which provide a nutrient source to an ...

of the bertam palm. This nectar contains one of the highest alcohol concentrations of all natural foods. The pen-tailed treeshrews did not show any signs of intoxication, although they frequently consumed large amounts of this nectar, equivalent of 10–12 glasses of wine adjusted to body weight with an alcohol content up to 3.8%. Measurements of a

biomarker In biomedical contexts, a biomarker, or biological marker, is a measurable indicator of some biological state or condition. Biomarkers are often measured and evaluated using blood, urine, or soft tissues to examine normal biological processes, ...

of alcohol dehydrogenase suggest that they may be metabolizing it by a pathway that is not used as heavily by humans. Their ability to ingest high amounts of alcohol is hypothesized to have been an evolutionary adaptation. How pen-tailed treeshrews benefit from this alcohol ingestion or what consequences of consistent high blood alcohol content might factor into their physiology is unclear.

Taxonomy and evolutionary history

The Ptilocercidae are a family within the order Scandentia. Numerous morphological and genetic differences support the classification of the Ptilocercidae as a separate family from the rest of the treeshrews which diverged around 60 million years ago. Treeshrews are considered very close relatives of primates, with the colugos being closer to primates.

References

External links

Zelkowitz, R. 2008. Now That's a Party Animal
Mammals described in 1848 Taxa named by John Edward Gray Mammals of Borneo Mammals of Brunei Mammals of Indonesia Mammals of Malaysia Mammals of Thailand Treeshrews Taxonomy articles created by Polbot {{Mammal-stub