He has seen 48 chimp legs because 12 x 4 = <<12*4=48>>48
He has seen 32 lion legs because 8 x 4 = <<8*4=32>>32
He has seen 20 lizard legs because 5 x 4 = <<5*4=20>>20
He has seen 100 total legs because 48 + 32 + 20 = <<48+32+20=100>>100
He has to see 1000 tarantulas legs because 1100- 100 = <<1100-100=1000>>1000
He has to see 125 tarantulas because 1000/ 8 = <<1000/8=125>>125
#### 125