
By weight, which animal has the largest baby relative to body size?
Human childbirth is hard enough – imagine giving birth to a baby half your weight!
Asked by: Emily Cane, Newcastle
Despite a kiwi being about the size of a chicken, the female lays an egg that is about half her weight! It’s so big because it has an enormous yolk, which sustains the chick for the first week of its life. Here you can see some other animals that have enormous babies, as well as those that have teeny tiny offspring (with humans thrown in for good measure).
Kiwi egg (1/2)
Giraffe (1/10)

Beluga whale (1/17)

Human (1/22)

Elephant (1/26)

Giant clam (1/500,000,000)

Ocean sunfish (1/1,500,000)

Red kangaroo (1/100,000)

Honey possum (1/2,400)

Giant panda (1/900)

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