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Shrewsbury, Shropshire, United Kingdom
FSC Preston Montford has been an outdoor classroom since 1957 and is a Field Studies Council centre. We deliver curriculum related outdoor education by the experts; from pre-school to Masters level; for infants, school students, undergraduates and enquiring adults with an interest in the natural world. Courses for schools and individuals. A venue for others to use; with bed space for 130, catering facilities and 7 fully equipped teaching and meeting spaces.

Sunday, April 28, 2019

Frogs vs Toads: What is the difference?


If you’ve been anywhere near fresh water in the past few weeks, chances are you’ve come across a frog or two. Here at Preston Montford they’ve been popping up everywhere as they wake from hibernation and begin their quest to raise the next generation. As I rescued one unfortunate toad that had tumbled down a drain outside Caradoc classroom, I couldn’t help but wonder…what actually is a toad? Is it just a frog with an ugly complexion? How can I be a biology undergraduate and not even know the difference between a frog and a toad?

The answer is, like many things in biology (and life), it’s complicated. Frogs and toads are both amphibians, a class of vertebrates that usually spend their larval stage in water before metamorphosing into their air-breathing adult forms. If this isn’t crazy enough, amphibians are also the owners of some of nature’s most exciting skin, which can act as a secondary respiratory surface and may secrete predator-deterring toxins. The golden poison frog is the most poisonous vertebrate in the world, containing enough venom to kill 10 adult men!

Phyllobates terribilis, the aptly named golden poison frog. Source: https://upload.wikimedia.org/wikipedia/commons/thumb/6/6e/Schrecklicherpfeilgiftfrosch-01.jpg/786px-Schrecklicherpfeilgiftfrosch-01.jpg

Within the amphibians, the order Anura, literally translating to “without tail” in Ancient Greek, includes both frogs and toads. This distinguishes them from “tailed” amphibians such as newts and salamanders, but this is about as far as taxonomy takes us. There is a family of “true toads”, (Bufonidae), within this order which are grouped together based on DNA and skeletal characteristics, like their lack of teeth. However, there are several “true toads” that have an appearance more similar to frogs, and many frog species outside this group that most people would distinguish as toads. In short, it’s a massive grey area and you’d be forgiven for just collectively labelling them as frogs, (which would technically be correct).

So is that it? Are toads just frogs with wrinkly skin? Well, yes, and no. Despite the many similarities between them, there are several characteristics that are generally recognised as more frog-like or more toad-like. Frogs tend to have longer legs for jumping between ponds, whereas toads have shorter legs for walking and hopping on land. Toad spawn is also distinguishable from frog spawn in that the eggs tend to be laid in long chains rather than clusters. Some toads such as Nimbaphrynoides occidentalis don’t even lay eggs at all, but actually give birth to little, fully formed toadlets, skipping the tadpole stage entirely. As I mentioned earlier, true toads also do not have any teeth…which means yes, most frogs do. They’re pretty small though, and are used for gripping onto their prey, not gnawing on human fingers.

Long ribbons of toad spawn.
Source: https://i.ytimg.com/vi/aGwAgLHY-78/maxresdefault.jpg

Of course, it’s impossible to talk about any wild animal these days, without mentioning how they’re suffering at the hands of humans. Frogs and toads make up around 90% of the world’s amphibian species, almost half of which are now in danger of extinction. Habitat loss, climate change and pollution, as well as the threat of the parasitic fungus known as amphibian chyrrid means it’s not a great time to be a frog, and quick action is needed if we are to save these iconic animals. If you have the space in your garden you may want to consider building a pond. Make sure it has plenty of vegetation and shallow sides to help the frogs hop in and out. I’ve seen at Preston Montford that even the smallest ponds can support a wealth of amphibian life, so building one really does make a difference! Of course we aren’t all able to build ponds in our gardens, but we all have the power to make an impact, whether that’s by reducing our carbon footprint or by occasionally rescuing toads from unfortunate places.

If you want to learn more about frogs and other amphibians, why not check out our courses at https://www.field-studies-council.org/individuals-and-families/natural-history/animals/reptiles-and-amphibians.aspx?

By Hannah Lawson (Education Assistant).

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