Marmosets and tamarins:

Real life gremlins!

Would you believe that a species of monkeys that fit into your palm exists in the world? Perhaps not, but there is such a species.

In fact, the famous film producer, Stephen Speilberg's movie 'Gremlins' released in 1984, and World War II Pilot, Ronald Dahl's book 'The Gremlins' published in 1943 were both inspired by these tiny creatures, the marmosets and tamarins. Even the

 bard Shakespeare has referred to the marmoset in his literary work, the 'Tempest'.

These monkeys are an elusive species (difficult to catch hold of), hardly or never seen as they live only in South and Central America and that too, in the deep of the Amazon forest.

In all probability, this elusiveness was a contributory factor for them being nicknamed gremlins after the mythical creature by that name. However, the Satare Mare Indians in the region claim they have earned this name mostly because of their appearance and also mischievous behaviour.

They believe that these magical creatures are reincarnations of their children. They are familiar with these tiny creatures and it is to them that a wildlife film maker and biologist turned to when hunting for this species in the Amazon rainforest to make a movie.

During their search for the elusive golden white tassel ear marmoset, a hitherto unknown species that they had

spotted had later been named Satare Maues Marmoset, in honour of the Satare Mare Indians by scientists.

Both marmosets and tamarins are fascinating animals and are called New World Monkeys. They belong to the genus Callithrix with about 18 species. Many of these species are either threatened or endangered due to deforestation. They are also being caught for biomedical research, and to be sold as pets or zoo exhibits.

While most of the countries where the monkey species is found has banned the export of those animals, Bolivia, Panama and French de Guinea still permits the export of marmosets and tamarins which are in high demand.

Appearance

Marmosets and tamarins are the most diverse and colourful of the New World primates. They have fine silky hair

 which is multicoloured or marked. Each species has unique tufts, manes and moustaches. Their diminutive (small) size, which is between 18-20 cm in length, has earned them the title of 'the world's tiniest monkeys.'

They are rather primitive in appearance compared to other monkeys. These creatures have mostly claws instead of nails; only the big toe has a nail. Both types have tactile (relating to the sense of touch) hairs on the wrists and lack wisdom teeth.

Marmosets have long lower incisors that help them to chew holes in tree trunks and branches to get at the sap. Their brain layout too is considered to be primitive in comparison to other primates.

Their tails which are twice the length of their bodies are not prehensile (capable of grasping). They use their hind legs to hold on to the branches and trunks of trees and their claws act as safe anchors.

Like all monkeys, the marmosets and tamarins too have very humanlike eyes.

Social behaviour

Very agile (active) creatures, they are always crossing from tree to tree, running along branches at high speeds. As they are extremely active, they travel about 1.2 miles in a day.

They are social animals and live in families of about 15-20 individuals, including one or two females, unrelated males and young. Usually, the dominant female gives birth to twins or occasionally triplets. The newborns weigh only one or two ounces the most.

The males are very much involved in the upbringing of babies and even in the birth process. The father bites off the umbilical cord which joins mum and babe together, at birth. Whenever mum is not nursing the little ones, guess who looks after them? Daddy dear of course, so that the tired mum could take a break.

A very caring and considerate gesture, don't you think? When travelling about, not only the adult males, but

 also females other than the mother, and older offspring all lend a hand to carry the infants. Yet another display of caring and sharing, we humans certainly could take a leaf off their book!

Infants who become independent after 12 weeks are taught hunting and other skills by relatives.

Marmosets and tamarins are generally peaceful animals, but they do display some aggressiveness when it comes to territorial rights. They resort to calling, chasing, displaying and gesturing when other animals try to invade their territory which they scent mark. They also use their scent glands to communicate.

Both types of animals maintain close family relations by grooming each other. Grooming is believed to strengthen family bonds.

Eating and living habits

Even though mostly frugivorous (fruit eaters), they also eat insects, bird eggs and other small vertebrae, depending on the species. They get most of the minerals and nutrients they need to survive from fruits and sap of trees. Unlike the marmosets, the tamarins don't have sharp teeth and claws to chew holes in tree trunks.

So, they often obtain the sap they need when certain trees such as the parkia trees ripen and burst, letting out sap, they relish this sap. Marmosets and tamarins live among the thick foliage in the vertical forest by day, and sleep on hollow tree trunks at night.

They are mostly found living halfway between the ground and tree tops, they hardly come to the ground except when searching for insects. At the first sign

 of danger, they scuttle back to their hideouts among the foliage.

Some species of marmosets and tamarins

Bare-eared marmoset
Black tailed and black-pencilled marmosets
Buffy-tufted and Buffy-headed marmosets
Common marmoset
Pygmy marmoset (not endangered)
Silvery marmoset
White-fronted marmoset
Tassel-ear marmoset
Black-mantle tamarin
Emperor tamarin
Red-handed tamarin
Cotton-top tamarin
Mottle-faced tamarin
Bone-faced tamarin

Fact file

* Their body temperature is usually variable.It changes by up to 4 degrees celsius in a day.

* Majority of the species spends 25 per cent to 30 per cent of their time searching for food.

* Females have two litters per year and have fraternal(non-identical) twins most of the time.

* The forelimbs are shorter than the hind limbs, but most locomotion is quadrupedal.

* Hands and feet resemble those of squirrels.

* Marmosets and tamarins are arboreal (tree dwelling) creatures.

* Pygmy marmosets feed primarily on tree sap or gum.

More on the world's tiniest monkeys next week