[Aware (OP)]

I read somewhere that adult humans have about 10 trillion cells.  How many cells would a smaller organism like an ant have?   

[DrN]

The estimate that I have come across is based on the estimate you have found for a human - about 1 billion cells per gram of tissue.

This even takes into account the relative lighter weight and larger size of fat cells, which is possibly a significant factor in (human) body size.

so there you go: find an ant, weigh it, and let us know!

[chris]

Don't forget, of course, about the bacterial cells which all organisms carry? We're outnumbered, in cellular terms, 50 to 1 by the bugs living in and on us! That means that if there are 10,000 trillion cells in the average human (the accepted estimate), there must be at least 500,000 trillion bacteria and fungi!

Ants also carry bugs on and in their bodies and in the case of leaf-cutter ants this bugs (chiefly a species of pseudo-nocardia) provide their hosts with a useful supply of anti-fungal compounds to keep at bay poisonous invasive fungi, such as escovopsis. In this respect I suppose these really are "ant-i-biotics".  boom boom.

Here's a link to the podcast in which this story was discussed in more detail:

http://www.thenakedscientists.com/HTML/shows/2006.01.15.htm#2

Chris

Chris

[DrN]

thats true. The estimate of 1 billion cells per gram is presumably of relatively clean tissue, not awash with intestinal bugs! so that means the estimate through weighing an entire organism in grams and multiplying by 1 billion would be a total cell count of bug plus human! although bacteria are much smaller than mammalian cells, so its all getting a little complicated.

to take the tone down a level - I think I read that faeces was made up of something like 60 to 80% bacteria. so you could weigh your poo?? []