Everything you always wanted to know about frogs and toads...
There are three types of amphibians : Anura (meaning absence of tail – like frogs and toads), caudata (meaning with visible tail – like salamanders and newts ) and Apoda (meaning without legs – found in the tropics only).
Everything you always wanted to know about frogs and toads…
written by Nolwenn Gouezel
Monday, July 27th.
Who are the amphibians ?
There are three types of amphibians : Anura (meaning absence of tail – like frogs and toads), caudata (meaning with visible tail – like salamanders and newts ) and Apoda (meaning without legs – found in the tropics only).
Green Frog – Tiger Salamander- American Toad
Amphibians can live on land and water. The word amphibian is derived from the two Greek terms « Amphi » and « bios » which mean « both » and « life ».
Did you know ?
Amphibians are tetrapods (four-legged vertebrates).
They are ectotherms (cold-blooded). Their body temperature changes depending on the temperature of the environment, unlike mammals which internal temperature is constant.
They have a smooth skin without scales.
When did the first amphibians appear on earth ?
Amphibians are the oldest land vertebrates.
Ichthyostega was an amphibian species that lived in Greenland about 360 million years ago.
How long do frogs live?
Some species only live a few years, but many live 6 or 7 years.
However, some records have shown that in captivity, frogs and toads can live for a surprisingly long time.
Did you know ?
One European Common Toad has lived for a grand total of 40 years!
What do frogs eat ?
Tadpoles are omnivores (some are herbivores while even some cannibalize other tadpoles!). Adult frogs are carnivores.
Frogs eat mainly arthropods (such as insects) and molluscs.
Some species can eat fishes, tadpoles and also other frogs. Cannibalism is frequent!
Some other ones can eat mouses, grass snakes and even small birds! In general if it moves and can fit in the frog’s mouth it is bon apetite !
Green Frog tadpole (at a late stage)
Did you know ?
Frogs have teeth, but toads do not!
Frogs don’t use these teeth to chew their food; they are used to hold the food in place before they swallow it whole.
When frogs swallow a meal, they close their eyes which go down into the head!
The eyeballs apply pressure, helping to crush the prey and push the meal down the throat to the belly!
How do amphibians breathe?
Tadpoles have gills, similar to fish, and most adult frogs have lungs like yours.
However, amphibians have permeable skin that allows them to absorb both water and oxygen directly from the environment, directly through their skin.
Green Frog Tadpole – Adult Green Frogs
When it’s raining, why do we usually say it’s a good weather for frogs ?
Water can evaporate easily from their skin. Most amphibians can dry up and die in a few hours if they do not have access to water. So amphibians can go away from their wetlands at times when evaporation is minimized : at night and/or when it’s raining. Even though some desert dwelling species have evolved special ways of storing water in their bodies even in arid environments.
Do amphibians hibernate ?
Yes, they do !
When cold weather comes many frogs swim at the bottom of ponds and lakes, and stay partially buried in the mud. They stay in hibernation until the spring. They arm themselves with antifreeze to protect their tissues ! Some northern species can survive below 0°C, even until -5°C to -7°C. They use glucose in their blood as a kind of antifreeze that concentrates in the vital organs, protecting them from damage while the rest of the body freezes solid.
They wake up as the ice thaws as if nothing had happened !
Researchers actually study this phenomenon in the hope of applying it in the giving of organs conservation and also in the frozen food industry.
What is the biggest frog ?
The world’s largest frog is the Goliath Frog Conraua goliath, which lives in Cameroon (in West Africa). They can weigh over 3 kg (6.6 lbs). Their bodies can reach the size of nearly a foot (30 cm) long and with the legs outstretched can be almost three times that length!
Among the smallest frogs, there is the Cuban Eleutherodactylus iberia ; This frog measures in at only 10 mm (0.4 in) when fully grown!
How far can frogs leap ?
Frogs are one of the best leapers on the planet. Their hind legs are so strong they can jump up to twenty times their own body length in a single leap.
That would be like if you could jump 100 feet!
For more information :
http://www.hamline.edu/cgee/frogs/science/frogfact.html
http://www.savethefrogs.com/cool-frog-facts/index.html
http://allaboutfrogs.org/weird/general/whatisfrog.html
http://www.naturewatch.ca/english/frogwatch/pq/intro.html
http://www.carcnet.ca/
http://redpath-museum.mcgill.ca/Qbp/herps/herps.html
The frog team is growing larger. Welcome to the new volunteers!
Friday, July 24th. This week, three new volunteers have joined the Brandon Ballengée’s SAT team:
Nadège Allan, McGill University Wildlife Biology graduated
Nathalie Dion, photograph,
and Zoe Brunelli, Dawson College fine arts graduated
Our research continues
Bio-art from Society for Arts and Technology on Vimeo.
Wednesday, July 22nd. Since the end of June, once or twice a week, Brandon Ballengée and his SAT frog team have put on their boots. The mainly explored areas are South of Montréal within a radius of about100 km.
Field-trip in Brossard area in the South of Montréal – Green Frogs and Leopard Frogs – A Leopard Frog examined by Brandon Ballengée
Since the beginning of their research, hundreds of frogs have been caught in the fishing nets, to be examined on the spot and then released. Some of them, about twenty, are under observation at the SAT bio-lab. Some have a missing leg, missing segments, or a missing eye.
About an hundred of tadpoles have been collected, especially in hotspots (where the rate of observed abnormalities is higher than 5% in the whole frog population). The volunteers are taking care of them every day and they are looking closely at their development.
Green Frog with missing foot
The team has set some experiments up with some of these tadpoles, putting them with natural predators such as dragonfly nymphs (collected in the same area) or leeches.
Each experiment has its own identification number and the team writes everyday what happens on duty sheets.
American Toad tadpoles – Green Frog tadpole (at a late stage)
As frequently as possible, the team makes pictures, videos and scans of the tadpoles, frogs, toads and also predators.
This week, for the first time, some frogs without obvious signs of abnormality have been released in the same place where they were collected a few weeks ago. Also, some dragonflies have grown up and flown away…
Survey !
Tuesday, July 21st. As we want to inform you in the best way about amphibians and our research at the bio-lab, we would like you to answer the questionnaire in the next link :
Click Here to take survey
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Put on your boots! Get set! Go!
It’s raining…what a good day for frogs!
