Sure! Here are the tiniest species in each group:

Amphibian: The smallest amphibian is the Brazilian Gold Frog (Brachycephalus didactylus), which can grow to just over 0.5 inches (1.3 cm) in length.

Bird: The smallest bird is the Bee Hummingbird (Mellisuga helenae), which is native to Cuba and the Isla de la Juventud in Cuba. It weighs about 0.06 ounces (1.95 grams) and has a length of about 2.24 inches (5.7 cm).

Mammal: The smallest mammal is the Bumblebee Bat (Craseonycteris thonglongyai), which is also known as the Bumblebee Bat. It is found in Thailand and Myanmar and has a wingspan of about 6.7 inches (17 cm) and a weight of about 0.06 ounces (2 grams).
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