Question:
A student just brought a mother toad into our
classroom. She has the toad in a mixing bowl with thousands of eggs and
about a pint of pond water. Are these eggs fertilized? Do they become
fertilized in the female or after they are layed? Can we watch them
develop in our classroom? Is there any special water, lighting,
temperature, or plants I should include?
Replies:
I believe all toad eggs are externally fertilized while they are being laid,
with the pair together. I don't think the female would have laid the eggs
without the presence of a male to fertilize them - how did the student get
the female and the eggs? Try to get some details about where and how they
were collected, if the student saw or scared off and failed to catch a male
with the female then the eggs might be fertile. If so they should hatch with
very little effort on your part, a good size aquarium with a few duckweed or
other small water plants from the area would be fine, no special lighting or
temperature should be required. If they hatch you will have to find out
about feeding the tadpoles.
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