Strawberry poison dart frogs prefer mates that look like their parents

A new research paper published on strawberry poison dart frogs in Bocas del Torro found that one of the reasons we have polymorphism or so many different color forms within one species of frog.  Female tadpoles prefer to mate with males that have the same color as their parents (sexual imprinting), and males defend their territories more vigorously from other males that are the same color as their parents (rival imprinting). The researchers demonstrated this experimentally by using foster parents of different color forms to raise offspring, and then tested mate or rival preference of the adult offspring.

This process of sexual selection can lead to sexual isolation even in populations that live in the same places. From an evolutionary perspective this would be a rare example of sympatric speciation, or the evolution through natural selection without geographical isolation.

Read the paper here  Yang, Y., Servedio, M.R., Richards-Zawacki, C.L., 2019. Imprinting sets the stage for speciation. Nature 574, 99–102.

Frog Friday! Strawberry Poison Dart Frog


Look, but don’t touch! Strawberry poison dart frogs (Oophaga pumilio) are known for their strikingly beautiful skin colors. Their bright color serves as a warning to predators that they are toxic. This type of “warning coloration” is called aposematism.  In the wild Oophaga pumilio gets its toxicity from its diet of ants and termites. The frogs we maintain in captivity in our exhibit Fabulous Frogs of Panama are fed small crickets and fruit flies. This change in diet eradicates any trace of poison in these frogs when they are raised in captivity

Strawberry poison dart frogs are generally a small species, about 0.75 to 1.5 inches (20 to 40 mm) in length. They are also mostly diurnal, and can be heard calling in the flooded forest.There are many poison frogs in the Dendrobatidae family with slightly different distributional ranges that can be found in Central America and northern South America. The species Oophaga pumilio are found in Mesoamerican countries and Panama.

Did you know? An Oophaga pumilio look alike was recently discovered in Panama by STRI scientist Cesar Jaramillo with  Abel Batista and Marcos Ponce (UNACHI) and Andrew Crawford (Universidad de los Andes). This new species Andinobates geminisae is still being described. Click here for more information.

Post by Dara Wilson


A Family of Frogs

Strawberry poison dart frog

This species of poison dart frog is well known for its attentiveness to its children. (Photo by Mehgan Murphy, Smithsonian's National Zoo)

With Thanksgiving just past and Christmas around the corner, this is a time of year many people turn toward family. While frogs are not the most social of animals and certainly do not celebrate the holidays, they do have a wide range of ways to care for their young.

The vast majority of frogs and toads reproduce by laying eggs in streams, ponds, vernal pools, or any other body of water they can find in the spring. The American bullfrog (Rana catesbeiana) and spring peeper (Pseudacris crucifer) are two common examples native to the United States. In both species, males stake out territories on the edge of a pond and call loudly to attract females. Once they mate, the eggs are laid in or near the water. After this, mom and dad are basically out of the picture.

However, these tadpoles are perfectly capable of taking care of themselves. In some species, they gather in large groups, oftentimes with siblings. Amazingly, even in this mostly hands-off approach to parenting, family still comes first!

Now, we can head to some of the more dedicated parents of the amphibian world.

First up is a species of poison dart frog well known for their attentiveness to their children, the strawberry poison frog (Oophaga pumilio). This little frog is common in the rainforests of Central America, from Nicaragua to Panama. The eggs of the strawberry poison frog are not laid in the water so the males take up the duty of carrying water in their cloaca to keep the clutch of eggs moist. These dedicated fathers can even move around to take care of multiple clutches at the same time!

After one to two weeks, the eggs hatch and the female takes over care. She spreads out the tadpoles between small pools of water in bromeliads by carrying them on her back, giving each one its own pool. Finally, she will continue to care for the tadpoles by feeding them unfertilized eggs until they are large enough to begin metamorphosis.

Luckily, the strawberry poison frog is listed as a species of least concern by the IUCN because of its large and widespread population.

It cannot be said that all male frogs abandon their babies before they are adults. Darwin’s frog (Rhinoderma darwinii) is almost unique in the extraordinary effort males put into caring for their young.

After the eggs are laid and fertilized, the male stays around to guard the eggs. A few days before they hatch, he gulps them down into his vocal sac, where they will grow and develop all the way into adults. There are special glands in the male’s vocal sac that secrete food for up to 19 tadpoles that he may be carrying. Once they are old enough, the young hop out of dad’s mouth to start life on their own.

Darwin’s frog is currently listed as vulnerable by the IUCN due to habitat destruction in its native country of Chile.

As you can see, not all frogs take the hands-off approach our native species do in the United States. Some frogs are very dedicated parents. This season at dinner, ask yourself (or your family!): Are we really so different from frogs?

– Andrew Franks, Zoo New England


I come in all shapes and sizes.


Strawberry Poison Dart Frog (Oophaga pumilio)
Strawberry Poison Dart Frog (Oophaga pumilio)

Cute Frog of the Week: April 11, 2011

The strawberry poison dart frog, Oophaga pumilio, is an amazingly beautiful little creature that normally reaches only 17 to 24 mm in length. Even though these cuties are tiny, their poison is potent. Like other poison dart frogs, skin coloration is this frog’s protection mechanism, indicating its toxicity and telling predators to stay away. This species has at least 15 different morphs, or forms, and can range in color patterns from blue with no spots to olive green and yellow with black flecks. In one of its most common forms, also known as the “blue jeans form,” the head and body of the poison dart frog are bright red or orange, with blue or black lower parts, giving the illusion that this tiny cutie is wearing pants! Males also have a special tan-grayish vocal pouch under the throat, which they use to defend their territory in the humid lowlands and forests of Costa Rica, Nicaragua and Panama.

These guys are fiercely territorial, sometimes defending territory that is up to 3 meters apart from other males! If someone provokes them or enters their “hopping” grounds, they aren’t afraid to challenge their opponents to a wrestling match. Another interesting fact about these dart frogs is that when it comes to breeding, the females really wear the pants. The females take matters into their own hands and approach the males to initiate breeding. Once the female has laid her eggs, it’s up to the male to tend to the clutch and keep them moist by—are you ready for this?—emptying  his bladder on them until they hatch. The females will then carry the tadpoles on her back to small pools in bromeliads and will feed the offspring  by laying unfertilized eggs in with the tadpoles as their primary food source. Both parents invest some serious time and resources in raising their young. Sounds like they deserve the “Parents of the Year” Award, right? While these brightly colored beauties do face threats, such as habitat loss and over-collection for the pet trade, there is some good news: These cuties are listed as least concern by the International Union for Conservation of Nature because of their wide distribution, tolerance of a degree of habitat modification and presumed large population.

Hop on, little guys!

Photo credit: Mehgan Murphy, Smithsonian’s National Zoo

Every week the Panama Amphibian Rescue and Conservation Project posts a new photo of a cute frog from anywhere in the world with an interesting, fun and unique story to tell. Be sure to check back every Monday for the latest addition.

Send us your own cute frogs by uploading your photos here: