Why Is the Kiwi's Egg So Big?

Kiwis also have a larger brain than other birds their size.<p>The causes and consequences of this are worth investigating.<p>A lot of animals have an architecture where they can’t carry a large brain, so a slightly larger brain is more of a hindrance than a help.<p>Bipedal animals can balance a heavier brain on their upright frame. But flying animals can’t afford too much extra weight.<p>I’m not sure what they do with the extra brain cells, but I suspect that their specially evolved nostrils would benefit from a powerful processing unit.<p>(Pigs for example have a large brain both in comparison to their body and in comparison to all other animals. I think the extra processing there is largely to support their incredible proboscis. Eg their legendary truffle hunting skills.)<p>I think our early human ancestor’s big brain was particularly useful for visual processing to assist with bipedal running&#x2F;hunting.

Today I learned the distinction between the kiwi bird and the kiwifruit <a href="https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Kiwifruit" rel="nofollow">https:&#x2F;&#x2F;en.m.wikipedia.org&#x2F;wiki&#x2F;Kiwifruit</a><p>I had always thought the latter to be a New Zealand fruit that is the source of the name &quot;kiwi&quot;.<p>No, kiwifruit is Chinese. The more you know.

I’ve read somewhere that Kiwis are in the running for being one of the closest genetic descendants &#x2F; relatives of the T. rex and if they ever get off New Zealand and are relieved of the island dwarfism pressure…

In summary, they thought it was an evolutionary anachronism, a large egg left over from a larger body size because of assumed relationships with larger ratites like Moas. But subsequent genetic and fossil research challenged that.<p>The article mentions an emerging view it is about &quot;precocity&quot; - larger and better developed babies, and extra yolk being able to provide nutrition to the baby for longer.

Feels like the animal kingdom opposite of the panda--adults weigh upwards of 300 pounds, but baby panda birth weights are just under 1&#x2F;3 of a pound.

The Save the Kiwi trust mentioned on a Kiwi release day that when releasing Kiwis back into the wild there&#x27;s a weight that the Kiwi must reach (1kg) before having a chance to survive against ferrets, rats, and stoats.<p>Perhaps the larger egg ensures a reduced exposure time between birth and 1kg for young Kiwis, which has helped those with larger eggs propagate more successfully?

Maybe it&#x27;s handling the eggs that taught the Kiwis rugby

Why does the Porridge Bird lay its egg in the air?<p><a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=lmWFrMq3qNY&amp;t=1457s" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=lmWFrMq3qNY&amp;t=1457s</a>

This led me down a ChatGPT rabbit hole of trying to figure out how long it would take kiwis to convergently evolve into humanoids…<p>Unrelated, I’m starting a new co called “Super-Kiwi” — time-to-market is ~200-300 million years.