# Do humans have the lowest infant mortality rate of all animals, even before modern medicine? **URL:** \ **Category:** Factual Questions\ **Created:** [September 9, 2018, 7:20pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060 "2018-09-09T19:20:22Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![kk\_fusion](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kk_fusion/32/15276_2.png) [@kk\_fusion](https://boards.straightdope.com/u/kk_fusion)\ **Post date:** [September 9, 2018, 7:20pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/1 "2018-09-09T19:20:22Z")
What it says in the title. Or going the other way, are there any domestic animals that, given intensive veterinary care, achieve greater infant survival rates than humans? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [September 9, 2018, 7:44pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/2 "2018-09-09T19:44:45Z")
I would assume that the infant mortality rate in pre-modern humans to be relatively higher than in many other mammals, due to the difficulty of birth because of the large infant head size compared to the birth canal. Non-human mammals don’t often die in childbirth, which was a major cause of women (and their babies) until very recently. Likewise, when humans began to live in dense populations the infant mortality rate probably went up due to infectious diseases, which only take hold in such circumstances. ---
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [September 9, 2018, 8:13pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/3 "2018-09-09T20:13:15Z")
My understanding is that a big part of the spread of infectious diseases is animal husbandry and humans living in dense areas. These allow infections to spread between humans as well as between humans and other species. A more solitary species would probably have lower rates of infectious diseases. Then again they may have a higher rate of death by predators. According to this, various primates have rates of child mortality about the same as humans in pre-industrial times. Around 50%. > **[2010-01935-008.pdf](https://psycnet.apa.org/fulltext/2010-01935-008.pdf)** ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [September 10, 2018, 5:04pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/4 "2018-09-10T17:04:56Z")
The first thing we’d have to do is define “infant mortality” in a way that can be applied across species with very different lifespans and life cycles. Is it just a death in the first x% of the total lifespan? Something to do with sexual maturity? Do eggs that get eaten count as infant mortality? For animals that have a larval stage, is any death in the larval stage infant mortality? Depending on how you answer those questions, then you might get different answers. Very generally, I would expect larger animals that have longer gestation and fewer young per birth to have lower infant mortality. Just mathematically, if they had higher infant mortality, there wouldn’t be enough individuals making it to breeding age. Humans are on the higher end of that scale, but not at the very top. ---
**Author:** ![kk\_fusion](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kk_fusion/32/15276_2.png) [@kk\_fusion](https://boards.straightdope.com/u/kk_fusion)\ **Post date:** [September 12, 2018, 7:23am UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/5 "2018-09-12T07:23:05Z")
> [@iamthewalrus\_3](#): > > Do eggs that get eaten count as infant mortality? For animals that have a larval stage, is any death in the larval stage infant mortality? Yes and yes. I guess we’re already down to only mammals? That also gives a clear cutoff age for infants: as long as they’re being teat-fed. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [September 12, 2018, 12:00pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/6 "2018-09-12T12:00:25Z")
> [@iamthewalrus\_3](#): > > Very generally, I would expect larger animals that have longer gestation and fewer young per birth to have lower infant mortality. Just mathematically, if they had higher infant mortality, there wouldn’t be enough individuals making it to breeding age. This would have been my guess too. If you have a litter, or lay hundreds of eggs, it’s less important for the survival of the species that a high percentage of them survive. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [September 12, 2018, 2:10pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/7 "2018-09-12T14:10:09Z")
> [@Thudlow\_Boink](#): > > This would have been my guess too. If you have a litter, or lay hundreds of eggs, it’s less important for the survival of the species that a high percentage of them survive. [This is r vs K](https://en.wikipedia.org/wiki/R/K_selection_theory). ---
**Author:** ![Ashtura](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ashtura/32/2963_2.png) [@Ashtura](https://boards.straightdope.com/u/Ashtura)\ **Post date:** [September 12, 2018, 2:28pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/8 "2018-09-12T14:28:00Z")
> [@kk\_fusion](#): > > Yes and yes. I guess we’re already down to only mammals? > > That also gives a clear cutoff age for infants: as long as they’re being teat-fed. I breed rats and mice. I almost never have a litter where at least one of the babies isn’t already dead or get eaten by the mother shortly thereafter (more with the mice). Then again, the number of pups regularly goes into the teens. ---
**Author:** ![Dead\_Cat](https://avatars.discourse-cdn.com/v4/letter/d/9fc29f/32.png) [@Dead\_Cat](https://boards.straightdope.com/u/Dead_Cat)\ **Post date:** [September 12, 2018, 4:59pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/9 "2018-09-12T16:59:43Z")
> [@Colibri](#): > > …childbirth, which was a major cause of women… In the interests of combating sexism on the boards, I feel I should point out that childbirth was also a major cause of men. ---
**Author:** ![penultima\_thule](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/penultima_thule/32/3833_2.png) [@penultima\_thule](https://boards.straightdope.com/u/penultima_thule)\ **Post date:** [September 13, 2018, 1:42pm UTC](https://boards.straightdope.com/t/do-humans-have-the-lowest-infant-mortality-rate-of-all-animals-even-before-modern-medicine/821060/10 "2018-09-13T13:42:34Z")
It’s such acts of truly selfless dedication to the cause of human enlightenment which make the SD what it is. 😃