I think if it was a surprise en masse attack we wouldn't stand a chance...but if there was some warning, or if it was gradual and prolonged we'd use
flamethrowers on the insects and bullets and bombs etc on everything else and we;d win...there wouldn't be much food left though so in the long run
would it really be winning?
Yea, if we were able to survive the attacks we would be low on food and the damage done by the animals as well as us would be catastrophic. It really
makes you think how lucky we are to have most animals passive towards humans.