Thanks guys - I think I was lucky by finally finding a strategy that worked.

Once I got Level 2 harvesting, every night I'd set one researcher and all the rest to farm and leave the game on Slow but switched on in the cradle while I slept. This really got the food up and I could do more research and have babies while I was awake and keeping an eye on it.

Like I said, I started the game at this level loads of times and never got too far. In two of the earlier starts, I got the whale pretty early on, and took the food option so I thought I'd be able to get past the breed versus food problem, but it never worked.

I've now got 1 GC, two doctors and 61 farmers - it's funny watching the queues to water the crops!