This scavenger hunt focuses on frog adaptations and how they are shaped by their environments. We will be looking at four different members of the frog family, which contains true frogs (amphibious), tree frogs (arboreal) and toads (terrestrial). All of these types of frogs are related and highly genetically similar, but have developed different adaptations to suit their lifestyles and environments. It is a common misconception that frogs and toads are completely separate species but in fact they are highly related and differ mostly in their preferred habitat. All can be referred to under the blanket term of “frog.” In other words, not all frogs are toads but all toads are frogs.
The four frogs we are focusing on are all from very different environments. The Lake Oku Clawed Frog and the Surinam Toad, prefer to spend most of their time in the water. The Vietnamese Mossy Frog and the Green Tree Frog prefer to live on vegetation near the water’s edge. This fundamental difference in habitat creates anatomical variation between the frogs.
The Lake Oku Clawed Frog (Xenopus longpipes) is a very unique species. It is only found in one specific crater lake (Lake Oku) completely isolated from all other bodies of water in Northwestern Cameroon. These frogs have an incredibly small body size (around three centimeters) and have developed coloring precisely to match the surrounding sediments. They have four webbed feet, which are unusually narrow for a fully aquatic amphibian. Therefore, they can’t swim as fast as most water-dwelling frogs. This likely developed as a response to a lack of predation. The claws are used to fend off competitors and tear food apart.
The Green Tree Frog, sometimes called the American Tree Frog (Hyla cinerea), is a relatively common frog found across the Southeastern United States and around the gulf of Mexico. These frogs tend to live in the greenery around water as opposed to in the water directly. They are commonly found in swamps and along riverbanks. These frogs grow to an average of 6 centimeters long and range in color from yellow to deep green. Their toes are long and mostly separated, making them ideal for clinging to reeds and climbing through underbrush.
The Vietnamese Mossy Frog (Theloderma corticale), as its name suggests, is found in the northern forests of Vietnam. They typically live in damp limestone caves and along the rocky banks of creeks. These frogs greatly resemble a clump of moss thanks to their green color, black spots, and visible tubercles. Even their eyes with green and black unique coloring allows it to blend effortlessly into its surroundings. . They grow to around 8 centimeters and are able to roll themselves into a ball as a defensive mechanism, emphasizing their already stone-like appearance. Their toes are long with round suction pads at the tips, perfectly designed for sticking to the slippery banks of the stream.
The Surinam Toad (Pipa pipa), unlike most toads, spends the majority of its life in the water. It earned the moniker of ‘toad’ as a result of its rough skin and large size (10-20 centimeters on average). This toad is widely known for its unique reproductive habits; fertilized eggs actually embed in the back skin of the mother where she incubates them until they hatch. Their bodies are extremely flat and angular, which allows them to blend effortlessly with the fallen leaves along the water’s shallow edges. As a result, they can surprise and ambush their prey as it travels by. The toad does not have teeth or a tongue, so the toad’s large gaping mouth is useful for catching prey and for swallowing it in one bite.