Of course what is a biologist going to use mesh to do...make cars?
Here are some of my first attempts at mesh modeling in Second Life. The mushrooms weren't too bad in terms of cost to upload and for land impact..but the green Equisetum inspired plant cost 30$L to upload the model. I wasn't taking particular care to optimize the mesh. Probably wouldn't have been too expensive but I extruded the mesh in the tops to get that texture and I think that is most of the cost.
But sounds like another reason to go to an Open Sim grid.