Want To Hear Some Titi Monkeys Sing A Duet? Their Songs Could Soon Be Lost To Extinction

The musical Mato Grosso titi monkey has been named one of the 25 most endangered primates in the world.


Rachael Funnell


Rachael Funnell

Writer & Senior Digital Producer

Rachael is a writer and digital content producer at IFLScience with a Zoology degree from the University of Southampton, UK, and a nose for novelty animal stories.

Writer & Senior Digital Producer

mato grosso titi monkey
"This one goes out to all the primates in peril," - Mato Grosso titi monkey, 2022. Image credit: Leandro Jerusalinsky via Re:Wild

A monkey whose species was only formally identified four years ago has joined the 25 most endangered primates in the world, according to a new “Primates In Peril 2022 – 2023” report. It names the Mato Grosso titi monkey (also known as the Groves’ titi monkey) as one of four species from Brazil to join the regrettable register.

The critically endangered Mato Grosso titi monkey, first described in 2019, is a 900-gram (two-pound) primate from the Brazilian Amazon, known for singing duets with fellow titis. The acapella arrangement (an example of which can be heard in the below video) could arguably do with a little work, but the world would certainly be a poorer place without it.


Image credit: Leandro Jerusalinsky via Re:Wild. Titi monkey recording credit: P Adret et al 2018CC BY 4.0

As monogamous animals, they’re also known to intertwine their tails when together – and in Mato Grosso titi monkey families, it’s the males who do much of the infant care. Unfortunately, they live in an area of the Amazon which overlaps with the Brazilian Cerrado ecosystem, considered one of the world's most threatened biodiversity hotspots.

One of the Mato Grosso titi monkey’s biggest threats is deforestation, something affecting much of the Brazilian Amazon where land is cleared for the cattle industry. The titis' home sits within one of the worst affected areas, and things could get worse as an ordinance is currently being considered that would remove the need for landowners in Mato Grosso to protect at least 80 percent of their native vegetation.

"We hope that the inclusion of the Mato Grosso titi monkey on the world’s 25 most endangered primates list is a wake-up call to the lawmakers of Mato Grosso who have the opportunity now to instead protect this endemic species," said Leandro Jerusalinsky, head of the National Center for Research and Conservation of Brazilian Primates, in a statement sent to IFLScience by Re:Wild.


"The Mato Grosso titi monkey is the perfect candidate to become the flagship species for Mato Grosso and there is no doubt that by conserving this species, other wildlife, including threatened primates, will benefit."

The renewed message of the need to protect the titi monkey comes with the announcement of the biennial Primates in Peril report, a collaboration from the IUCN SSC Primate Specialist Group, the International Primatological Society, and Re:wild. It aims to champion species in need of our help in a list that spans Africa, Asia, and the Neotropics.

Its goal isn’t to spread doom and gloom, but instead to facilitate action while there’s still time to turn things around.

"Just because a primate ends up on the 'Primates in Peril' list doesn’t mean that the situation is hopeless," said Russ Mittermeier, Re:wild’s Chief Conservation Officer and chair of the IUCN SSC Primate Specialist Group.


"In fact, our goal with the report is to highlight those species, like the Mato Grosso titi monkey, where there are conservation opportunities. We hope this report helps spur the necessary resources, research and political will to reverse the decline of these species, those they share their home with, the ecosystems in which they live, and the health of the planet overall."


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