Frog vs Toad
1. Classification
There is not a major distinction between the taxonomy of the frog and of the toad as they are very biologically similar. Both of them belong to the Amphibia class (meaning twin-life to represent their time on both water and land) and the Anura order (meaning tail-less).i They also share the same 3 suborders under the Anura classification. These are Archaeobatrachia, Mesobatrachia and Neobatrachia. All species of frogs and toads alive today are a part of the Neobatrachia suborder as the other two describe older, now extinct frog and toad species. This is where the taxonomic similarities end though as they belong to different families within their shared suborder. The toads are represented in the families Bufonidae, Bombinatoridae, Discoglossidae, Pelobatidae, Rhinophrynidate, Scaphiopodidae and Microhylidae.ii Frogs are actually found in a total of 33 different families due to their wide variety of diversity as there are a total of about 4,810 species. However, the groups of Leptodactylidae with about 1,100 species, Hylidae with about 800 species and Ranidae with about 750 species are the richest groups.iii
2. Skin
One of the biggest major differences between a frog and a toad is with their skin. Both of them have skin that is permeable to water meaning that they can absorb moisture through their skin. This allows them to not have to drink when they are thirsty they can just hop into a puddle, pond or stream. In addition to being permeable to water, their skin is permeable to air meaning that they can also breathe through their skin. This allows them to be able to hibernate for months at the bottom of a pond during the winter because they can simply absorb the dissolved oxygen in the water.iv However, remarkable as these features are, they are the extent of the similarities with their skin. A toad’s skin in noted for its rough, bumpy and dry skin. While their bumps are commonly called warts, they are actually not like infectious warts as they are present on all toads, including healthy ones. They are simply called warts due to their appearance being similar to infectious warts.v Unlike toads, frogs generally have smooth skin that is free of any warts or bumps. In addition to this difference, a frog’s skin is generally moist at all times where a toad’s will be generally dry. Toads are also able to secrete a toxin through their skin which is an ability that a frog lacks, although there are a few exceptions to this. These toxin glands are typically found at the rear of the head and back and the secretion is slippery allowing them an advantage when escaping from predators.vi
3. Appearance
Aside from their skin, frogs and toads have other physical characteristics which are different. The first is with their eyes. A frog is known for his bulging eyes and the reason they stick out so far is that it allows them to look in all directions. They have a greater field of vision than the toad, whose eyes tend to face forward.vii The frog eyes provide binocular vision with a total visual field of almost 360 degreesviii which is a feature that the toad generally lacks. The body shape of a frog is also generally slim with very long legs that allow them to leap quite far. The body shape of a frog is generally fatter with much shorter legs which allow for shorter hops rather than the long leaps.ix Frogs also have long tongues which help as their aim is only adequate. Toads have a much shorter tongue but their aim is much better when they try to catch food.x Toads are also toothless, whereas frogs have small upper teeth generally. These are called pedicellate teeth in which the crown is separated from the root by fibrous tissue. Their lower jaw lacks teeth, but some frog species have cone shaped bony projections called odontoid processes which function much like teeth do.xi The appearance of the eggs in both species is also distinct. A frogs’ eggs are usually laid in clumps, in single form or as a floating film. Toad eggs are usually laid in long strands.xii
4. Habitat
Another major difference is the habitat in which both a frog and toad live. Since a frog must generally maintain a moist skin, they are required to live near or in water and rarely stray far from a river, stream, lake or pond. They also live on every continent except Antarctica. The greatest diversity occurs in temperate climate regions such as Europe, though they can even be found in deserts, though with certain adaptations which make it possible for them to survive in such an arid climate.xiii Unlike frogs, toads do not need to live near water as their skin is typically dry. They can roam much farther away from water than the frog.xiv
5. Predators
Frogs and toads also have a difference in the amount of known predators for each. Frogs, aside from some exceptions) generally have a much higher amount of predators. This is due to the fact that they generally do not have the toxic glands that a toad has and their skin is smoother, allowing a predator to more easily bite down on them. The toad, with it’s tougher skin and the presence of their toxic glands, has far fewer predators.xv