40 Fun Facts About Squirrel Monkey

Squirrel monkeys rub which liquid over their own skin, a habit thought to help them cool off?

Urine is the liquid: the habit, called urine washing, peaks on the hottest days, so evaporation is thought to cool the monkey. It may also carry scent signals.

Relative to body size, squirrel monkeys hold which record among all primates?

Largest brain is the record: weight for weight, a squirrel monkey carries more brain than any other primate, humans included.

Unlike spider and howler monkeys, an adult squirrel monkey uses its long tail mainly for what?

Balance is the tail's job: it works like a tightrope walker's pole as the monkey races along branches. Only newborn infants can grip with it.

The squirrel monkey's black-and-white face inspired which grim phrase in its German, Dutch and Swedish names?

Death's head is what Totenkopf means in the German name Totenkopfaffe: the white mask and dark muzzle look like a skull.

Squirrel monkey Miss Baker, who survived a 1959 US rocket flight, was first bought from what kind of place?

A pet shop sold her, along with 25 other squirrel monkeys, to be tested as flight candidates. She stood out for her gentle manner and earned the nickname TLC.

Central American squirrel monkeys knock which animals out of folded-leaf shelters to eat them?

Bats are the target: the monkey spots a tent-making bat's folded leaf, climbs above it and jumps onto the tent to dislodge the sleeper. A bat too slow to fly off gets eaten.

Central American squirrel monkeys, wary of birds of prey, have given alarm calls at which harmless things?

Small airplanes set them off, as do falling branches and big leaves: anything shaped like a raptor overhead sends the whole troop diving for cover.

Escaped and released squirrel monkeys formed wild colonies from the 1960s onward in which US state?

Florida has had five such colonies, one released at Silver Springs around 1960. Cold winters and trappers wore them down, and by 2021 a single monkey was left.

Which colorful rainforest birds are known to prey on infant Central American squirrel monkeys?

Toucans take newborns, as do tayras, opossums, coatis and snakes. Only about half of the infants survive their first six months.

In 2009, gene therapy given to adult male squirrel monkeys appeared to cure which condition present from birth?

Color blindness of the red-green kind is natural in every male squirrel monkey. After a human pigment gene was delivered to their retinas, treated males passed color vision tests.

Squirrel monkeys, which live in hot and humid forests, can sweat only through which parts of the body?

Palms and soles are the only places a squirrel monkey sweats, which is why its hands and feet can feel damp to the touch.

Which magazine put squirrel monkey Miss Baker and her crewmate Able on its cover in June 1959?

Life ran the pair on its cover after a US Navy ship recovered their capsule from the Atlantic. Miss Baker later drew 100 to 150 letters a day from schoolchildren.

Miss Baker, the squirrel monkey who rode a US rocket in 1959, is buried at a rocket museum in which state?

Alabama is home to the US Space & Rocket Center in Huntsville, where she lived from 1971. She died in 1984, by then the oldest squirrel monkey on record.

In 1962, caretakers of space-flown squirrel monkey Miss Baker held which ceremony for her and Big George?

A wedding paired her with Big George. After he died in 1979 she was married again, to a monkey named Norman, and tore off her white bridal train within seconds.

Which Space Shuttle carried two squirrel monkeys and 24 rats into orbit on the Spacelab 3 mission in 1985?

Challenger flew the animals in special cages for seven days. The two monkeys had no names, only numbers: No. 3165 and No. 384-80.

South American squirrel monkeys often feed alongside which bigger monkeys, gaining from their predator alarms?

Capuchins lead them to the richest feeding trees and add extra eyes to spot danger. The Central American squirrel monkey is the exception: it rarely joins its capuchin neighbors.

The Central American squirrel monkey lives wild in just two countries: Panama and which other?

Costa Rica holds most of them, along its Pacific coast. The species has fallen from about 200,000 animals in the 1970s to fewer than 5,000.

The black squirrel monkey has one of the smallest ranges of any primate, all inside one reserve in which country?

Brazil's Mamirauá reserve holds the entire species, squeezed in where two rivers meet and sharing the forest with two other kinds of squirrel monkey.

The black squirrel monkey lives only in várzea, a type of forest shaped by which yearly event?

Seasonal flooding can put around 35 feet of water in the forest, and floods that last unusually long are a threat to the monkeys' tiny home.

Before breeding season, male squirrel monkeys undergo which change that females seem to favor?

They grow larger as hormone levels surge in the months around breeding, and the bulkiest males tend to win the most matings.

Central American squirrel monkeys spend two-thirds to three-quarters of each day on which activity?

Foraging for food fills most of the day, and a troop covers 2.5 to 4.2 km doing it, without ever splitting into separate search parties.

Where does a newborn black-capped squirrel monkey spend almost all of its first few days?

On its mother's back is where the newborn clings, barely moving, at the start. Adult males take almost no part in raising the young.

Most squirrel monkey species live in the rainforest basin of which great South American river?

Amazon forests hold nearly every species, mostly in ranges that sit side by side without overlapping. One outlier lives far away in Central America.

Squirrel monkey species are sorted into two groups by the white arches above their eyes, named after which styles?

Gothic and Roman are the labels: a pointed white arch over each eye marks one group and a rounded arch the other, a split first drawn in 1964.

Which pair of foods makes up most of the diet of wild squirrel monkeys?

Fruit and insects come first, but squirrel monkeys will also take eggs, flowers, buds and the occasional small animal.

Besides the pet trade, common squirrel monkeys have been captured in large numbers for which other purpose?

Medical research has used squirrel monkeys widely, including in aerospace tests. Despite the captures, the common squirrel monkey is not considered threatened.

In undisturbed forest, a single troop of squirrel monkeys has been seen with as many as how many members?

About 500 is the upper figure for these giant troops, which can break up into smaller bands. A typical group numbers between 12 and 100.

Roughly how much does a full-grown male squirrel monkey weigh?

About 1 kg (2 lb) is the top of the usual range for males, and females are lighter still, at 500 to 750 grams.

When its usual meals run short, the common squirrel monkey turns to drinking which sugary liquid?

Nectar tides the common squirrel monkey over lean spells. It also gets most of its water from what it eats, topping up from tree holes and puddles.

Saimiri oerstedii, the Central American squirrel monkey, was named in honor of a naturalist from which country?

Denmark was home to both men involved: Johannes Reinhardt, who gave the species its name, chose it to honor his fellow biologist Anders Sandøe Ørsted.

Unique among squirrel monkeys, the Central American species has which arrangement between males and females?

Neither sex dominates in this unusually egalitarian monkey. In the South American species, either the males or the females hold rank over the other sex.

What is striking about when the infants of one Central American squirrel monkey troop are born each year?

All within one week: the females come into season at virtually the same time, so six months later a troop's babies arrive together, in February or March.

Before DNA studies, how was the Central American squirrel monkey thought to have reached its isolated home?

Brought there by people was the old guess, since its range is tiny and far from any relative. Genetics showed it has been a separate species for at least 260,000 years.

What are double-toothed kites, small forest raptors, after when they trail Central American squirrel monkey troops?

Prey the monkeys flush out is the prize: a moving troop scares small creatures into the open, and the birds tag along most in the wet season, when such meals are harder to find.

Fossils of Neosaimiri, a 12-million-year-old relative of squirrel monkeys, were found at La Venta in which country?

Colombia's La Venta fossil beds yielded the animal, whose teeth and skull link it to living squirrel monkeys. An even older relative, Dolichocebus, turned up in Argentina.

Squirrel monkeys, probably escaped or released pets, became an invasive species in the Tijuca Forest of which city?

Rio de Janeiro's city forest had a free-ranging group by 2009, and conservationists soon worried about the eggs of the endangered birds nesting there.

In Central American squirrel monkeys, which members usually leave the troop they were born into?

Maturing females move out, while males usually stay with their birth troop for good. In South American species it is the males, or both sexes, that leave.

In a Central American squirrel monkey troop, which members bear most of the duty of spotting predators?

The oldest males do most of the watching, and their vigilance matters most in birth season, when raptors loiter near the troop to pick off newborns.

Able, the crewmate of squirrel monkey Miss Baker on a 1959 US rocket flight, was which kind of monkey?

Rhesus macaque Able was born at a zoo in Kansas, while her tiny crewmate came from Peru. Able died days after the flight, during surgery to remove an electrode.

Space-flown squirrel monkey Miss Baker and her crewmate Able took their names from what?

A military phonetic alphabet supplied both names. The two monkeys were first called Alpha and Bravo, then renamed from the older spelling set that began Able, Baker.