Bird Week is a simple, cute action game where you control a mother bird and have to collect butterflies/insects to feed your baby birds until they are ready to leave the nest. Also avoid numerous predators that try to catch you. The simple gameplay is accompanied by below average graphics and rather annoying music and clearly aimed at kids. Wikipedia categorizes this game amongst "biological simulations", but I think that is really far-fetched. You can't influence development of anything at all.