Opposable thumbs allow us to firmly grip something with our hands, and it was long believed to be a human-only trait.
However, there are more than a dozen of species of animals with opposable thumbs in the wild, and today, we’ll be listing them down.
Animals with opposable thumbs:
- Giant Pandas
- East African Maned Rats
- Sulawesi Bear Cuscus
- (Some) Murids
- (Most) Birds
- Phyllomedusa Frogs
Animals with pseudo-opposable thumbs:
- Squirrel Monkeys
Animals with Opposable Thumbs
Scientific name (family): Chamaeleonidae
The reason chameleons are the only reptiles with opposable thumbs is to make it easier to climb on trees. They have completely adapted their body for an arboreal way of life.
They have five toes on each foot; on the front feet, they have two toes in the outer group and three toes in the inner group. Their rear feet contain three toes in the outer group and two toes in the inner group.
Because of these modifications, chameleons can climb more or less anywhere as they can fully grasp branches.
Scientific name (genus): Gorilla
Gorillas are animals with opposable thumbs like humans, and they’re one of the few species to pride themselves on that trait. These highly intelligent apes wouldn’t be able to utilize their gifts if they didn’t have opposable thumbs.
For example, they know how to use tools in the wild. They also pick their food (they’re mostly omnivorous), which is much easier with opposable thumbs.
All great apes have been documented using tools and simple weapons, which is why their grip is absolutely crucial.
Scientific name: Pan troglodytes
Not only do chimps have opposable thumbs on their hands, but the big toes on the feet of chimps are also completely opposable. Unlike humans, chimpanzees can grasp with both their hands and their feet.
They’re also more adapted to climbing than humans, as they can grab branches with both hands and feet.
Just like gorillas, chimpanzees have been observed to use tools in the wild and pick fruit, which is much easier with opposable thumbs. They’ll often use small twigs, similar to how we use forks, to dig up ants and other insects.
Scientific name: Phascolarctos cinereus
Koalas have made several adaptations for climbing and arboreal life. For example, they have very sharp claws to pick themselves up with, while they also have opposable digits.
Sometimes, two digits are fused together, forming one large finger.
These furry animals with opposable fingers use this modification for climbing, but also for grooming. Since their paws are large (given their size), koalas can grip both big and small branches.
5. Giant Panda
Scientific name: Ailuropoda melanoleuca
Interestingly, the hand of a giant panda is surprisingly human-like. They have a thumb and five more fingers, while the thumb is a modified bone.
This makes the panda the only bear with opposable thumbs, but also one of the largest animals with opposable thumbs.
Why does the panda have opposable thumbs, you ask? Well, they switched to a bamboo diet (they used to be omnivores a long time ago), and bamboo sticks are difficult to grasp if you don’t have opposable thumbs. Pandas evolved thumbs to make eating easier.
6. East African Maned Rats
Scientific name: Lophiomys imhausi
The East African maned rat is famous for being the only poisonous rodent, as it takes toxins from plants to deter predators from itself. However, people often forget he’s also one of the very few rodents with opposable thumbs.
These animals spend a lot of their time in trees, so they had to develop opposable thumbs for better grip.
When threatened, aside from screaming, it will cover itself with toxins, and the predator biting it will poison itself. It is the only mammal to do this, as far as we know.
7. Sulawesi Bear Cuscus
Scientific name: Ailurops ursinus
This species, endemic to Sulawesi and other close islands in Indonesia, is known for having opposable thumbs that make it easier to climb. It has three toes on one side and two toes on the other side of the hand.
Unfortunately, they are a vulnerable species. Their cousins, Talaud bear cuscuses, are another species of marsupials with opposable thumbs. Unfortunately, they’re critically endangered.
Scientific name (genus): Macaca
These monkeys with opposable thumbs have similar abilities to humans, as they can grip whatever they want and they hold objects with a thumb on one side and the rest of the fingers on the other.
This also helps them with climbing, although they spend most of their time on the ground. Since they’re mostly vegetarian, they have to pick fruits and seeds to eat.
This means that they’ll often raid crops or even steal from markets, which is when their fingers come in handy.
9. (Some) Murids
Scientific name (family): Muridae
There are over 1,300 species of rodents in this family, but only a select few have opposable thumbs or at least one opposable finger. These animals belong to the genera Hapalomys, Chiropodomys, Vandeleuria, and Chiromyscus.
They’re often referred to as ‘tree rats’ or ‘climbing rats’, as these small animals with opposable thumbs have evolved to climb more easily. They are very arboreal and they spend most of their life climbing for shelter.
Scientific name (family): Didelphidae
On their hind feet, opossums have no claw on their opposable thumb, which allows them to grip easily. Opossums don’t have opposable thumbs on their front feet, only on their hind feet.
Aside from the water opossum, which has webbed feet, all opossums have opposable thumbs. These mammals with opposable thumbs are not particularly arboreal, but they climb very easily and they’ll do it to escape predators (if playing dead doesn’t work).
Scientific name (genus): Pongo
Surprisingly, orangutans have hands very similar to our own – their opposable thumb is much shorter in comparison to their other fingers.
This means that they can get a good grip on small objects by locking their palms. This trait is rarely seen in animals other than humans.
Just like chimps, the big toe on their feet is opposable too, which makes climbing much easier. In comparison to humans, orangutans are much more flexible.
The joint in their hip is just as flexible as the joints in their shoulders and their elbows, providing them with improved mobility.
These animals with opposable thumbs and binocular vision have completely adapted their bodies to live in the trees.
12. (Most) Birds
Scientific name (class): Aves
We have to put a little disclaimer here, as no bird toe can be defined as a thumb. However, birds have opposable toes on their feet, with most birds having one finger in the back opposing three fingers in the front.
Because of this, they can easily stay on top of branches, while it’s also important for birds of prey because they need to get a good grip on their kill.
There are also examples of tridactylity and didactylity (three or two toes without an opposing toe) in birds, but that’s rarer.
13. Phyllomedusa Frogs
Scientific name (genus): Phyllomedusa
With all 16 species within this genus having opposable toes, it was impossible not to include these frogs on the list. They’re the only amphibians with opposable thumbs, and they need them for climbing.
These tree frogs have one opposable digit, which allows them to narrowly grip the branches they’re climbing on. Like most frogs, they’re incredible climbers, capable of jumping to great heights and staying stuck to seemingly flat, vertical surfaces.
Scientific name (family): Hylobatidae
Gibbons are monkeys that have opposable thumbs, and they’re the final entry when it comes to truly opposable thumbs (we’ll explain later). Their thumb is also shorter than all the other fingers, just like in humans and orangutans.
Apart from being excellent climbers (they have a ball-and-socket joint in their wrists, just like we do in our shoulders), gibbons need opposable thumbs for picking fruit, insects, flowers, and even bird eggs for food.
Animals with Pseudo-Opposable Thumbs
Pseudo-opposable thumbs aren’t as bendable and they can’t achieve the same grip as actual opposable thumbs. They’re still very helpful with climbing and gripping, but they’re not as well-developed.
Scientific name (superfamily): Lemuroidea
Lemurs are often listed as animals with opposable thumbs, but they’re actually animals with pseudo-opposable thumbs. They can’t move their thumb independently from the rest of the digits on their hands.
Despite that, lemurs are very agile animals – very good at leaping and climbing. Depending on the species, they can be very quick or very slow at climbing, while some of them are even good swimmers.
Their jumping abilities far outweigh their climbing abilities though, as indriidae can jump up to 33 feet from one tree to another. That’s something not even Tarzan could do!
Scientific name (subfamily): Lorinae
These secretive animals are only found in India, Sri Lanka, and a few other pockets around southeast Asia. They have five toes on their feet, with the big toe opposing the other four, enabling lorises to firmly grip branches and food.
They’re very slow movers, and they’re mostly active at night. Unfortunately, these nocturnal animals with opposable thumbs are endangered due to the loss of habitat.
Scientific name (subfamily): Cebinae
Not all monkeys have well-developed opposable thumbs, and capuchins are the perfect example of this. Even though they don’t have a problem with it and it doesn’t slow down their climbing and feeding, their thumbs aren’t truly opposable.
Just like their cousins, these monkeys with pseudo-opposable thumbs use tools, such as sticks to dig nuts and catch ants, and containers to hold water.
They’re even smart enough to bang one stone against another (something that would be impossible with non-opposable thumbs) like a hammer and a chisel. Moreover, these primates display a clear hand preference, just like humans.
18. Squirrel Monkeys
Scientific name (genus): Saimiri
Squirrel monkeys are incredible climbers and they can move through the trees so swiftly that they’re impossible to catch. This comes in handy when they need to run from falcons and snakes, which are their primary threats in the wild.
They have an opposable thumb on each hand, slightly shorter than the rest of the fingers.
It’s not entirely opposable, but it’s good enough to grip branches and swing around. Since they rarely grow past 14 inches, they’re some of the smallest monkeys in the world.
Scientific name (genus): Perodicticus
This African animal with opposable thumb is the final entry on our list. They have a rather odd hand – their index finger has receded throughout time, and they now only have a stump remaining.
The opposable thumbs aren’t entirely opposable, but they allow pottos to grab branches and climb.
They’re very silent climbers and they spend the majority of their life in the trees, with the majority of their diet being fruit and tree vegetation.