# Which species outnumber humans? **URL:** \ **Category:** Factual Questions\ **Created:** [August 20, 2013, 2:12am UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685 "2013-08-20T02:12:37Z")\ **Posts on this page:** 12\ **Page:** 2
**Author:** ![Ponch8](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ponch8/32/9883_2.png) [@Ponch8](https://boards.straightdope.com/u/Ponch8)\ **Post date:** [August 20, 2013, 8:03pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/21 "2013-08-20T20:03:03Z")
> [@GusNSpot](#): > > I heard we have the highest number of heart beats in an average life span than other animals. I define animals in my mind in such a way that mean warm blooded. So using that criteria, total number of heart beats, what warm blooded mammal / animal has the longest life time in # of heart beats? I’d guess that certain macaw species would have many more heart beats. They can live to almost 100, and [this website](http://www.lafebervet.com/avian-medicine-list/basic-information-sheets-for-the-macaw/) says large macaws’ heart rate is 275/minute (compared to maybe 60-80 for humans). ---
**Author:** ![NotDeadYet](https://avatars.discourse-cdn.com/v4/letter/n/22d042/32.png) [@NotDeadYet](https://boards.straightdope.com/u/NotDeadYet)\ **Post date:** [August 20, 2013, 8:31pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/22 "2013-08-20T20:31:03Z")
Ants, cockroaches, mosquetos, house flies, fleas, lice, … Lts and lots of things outnumber humans. ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [August 20, 2013, 9:28pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/23 "2013-08-20T21:28:49Z")
> [@Bob\_Blaylock](#): > > I heard, somewhere, that the average human being has about ten times as many bacterial cells in his body as human cells. That can’t be right, can it? Aren’t most functional cells the same general size, give or take a bit (and ignoring a few outliers like massive single-cell funguses and the like)? I doubt I’m 90% bacteria by mass. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 20, 2013, 9:32pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/24 "2013-08-20T21:32:14Z")
> [@TimeWinder](#): > > That can’t be right, can it? Aren’t most functional cells the same general size, give or take a bit (and ignoring a few outliers like massive single-cell funguses and the like)? I doubt I’m 90% bacteria by mass. Bacteria are (generally) a lot smaller than our own cells - at least an order of magnitude smaller. ETA: For example, [this](http://www.theguardian.com/lifeandstyle/2013/mar/17/antibiotic-resistance-war-against-superbugs)page has a micrograph of a human blood cell and Staphylococcus together. ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [August 20, 2013, 9:45pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/25 "2013-08-20T21:45:53Z")
> [@nearwildheaven](#): > > Birds, fish, small mammals, insects, reptiles, amphibians - there are plenty of species that number more than 7 billion. Leave out invertebrates and I don’t think there are many. At best some small baitfish that live in dense aggregates like some species of anchovy might qualify ( but remember there are 144 species of anchovy, not one ). Move beyond fish and domestic chickens are about it I expect. ---
**Author:** ![Bob\_Blaylock](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_blaylock/32/3235_2.png) [@Bob\_Blaylock](https://boards.straightdope.com/u/Bob_Blaylock)\ **Post date:** [August 20, 2013, 10:23pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/26 "2013-08-20T22:23:45Z")
> [@TimeWinder](#): > > That can’t be right, can it? Aren’t most functional cells the same general size, give or take a bit (and ignoring a few outliers like massive single-cell funguses and the like)? I doubt I’m 90% bacteria by mass. No. Bacteria, in general, are much smaller and simpler than any human cells. Take another look at [this picture](http://microbewiki.kenyon.edu/images/1/16/20100926_180209_DentalPlaque.jpg). The few larger red objects are, I think, human epithelial cells. Human cells vary somewhat in size, but I think these are about typical. You can see that they are much bigger than the bacteria, which are the vast majority of the cells in this picture. ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [August 20, 2013, 10:42pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/27 "2013-08-20T22:42:40Z")
The most common wild species of bird is thought to be the red billed quelea- though it’s damn hard to find a good population estimate- numbers thrown around vary from 1.5 billion breeding adults (or maybe 1.5 billion pairs) to a possible maximum population of 10 billion individuals. Possibly at certain times of year they could briefly outnumber humans, but I’m not volunteering to count. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [August 20, 2013, 10:55pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/28 "2013-08-20T22:55:32Z")
MODERATOR NOTE **Bob Blaylock**. You’ve use your signature twice in this thread. One per thread is allowed, more is too much. **samclem** , moderator ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [August 20, 2013, 10:59pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/29 "2013-08-20T22:59:34Z")
> [@IvoryTowerDenizen](#): > > Here’s an article that tries to address your question. The consensus is the brown rat, but they also conclude its really hard to estimate. > > [Along With Humans, Who Else Is In The 7 Billion Club? : The Two-Way : NPR](http://www.npr.org/blogs/thetwo-way/2011/11/03/141946751/along-with-humans-who-else-is-in-the-7-billion-club) From the OP: > [@](#): > > What is the next largest animal to humans that outnumbers humans? Wouldn’t the answer be chickens from that source? Or are brown rats bigger than I’m imagining them? ---
**Author:** ![Longshanks](https://avatars.discourse-cdn.com/v4/letter/l/e480ec/32.png) [@Longshanks](https://boards.straightdope.com/u/Longshanks)\ **Post date:** [August 21, 2013, 12:19am UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/30 "2013-08-21T00:19:08Z")
Bed bugs probably. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 21, 2013, 1:09am UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/31 "2013-08-21T01:09:17Z")
The thing about heartbeats applies only to mammals, and you probably read it in an Asimov essay. ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [August 21, 2013, 10:39pm UTC](https://boards.straightdope.com/t/which-species-outnumber-humans/666685/32 "2013-08-21T22:39:06Z")
> [@Little\_Nemo](#): > > So chickens have us outnumbered… I hope they don’t find out! :eek: [Previous page](https://boards.straightdope.com/t/which-species-outnumber-humans/666685.md?page=1)