|MadSci Network: Zoology|
Some butterflies and moths prefer to lay eggs on the underside of a leaf. This is mostly for the purposes of protection. The eggs remains out of sight of some predators, and will also be protected from light (UV light can be damaging to insects, just like it is to our skin). Also by laying eggs on the underside of the leaf, the butterfly or moth gets a better leverage, because it has to curl its abdomen inwards while laying eggs.
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