Twin pets.

Question
Dear Kathleen

Can we trace Twin pets viz dog, cat, Horse, Fish, Bird etc?.

Example - Twin Goldfish.

Could they be both Twin males fishes, both Twin Female fishes, one Male, one Female Twin fishes?.

Thanks
Prashant

Answer
All animals in a litter or a brood of fish are fraternal twins. In fish identical twins would be hard to prove. Since we cannot see the development of the egg. In cats, dogs etc if the placenta has two cords coming from it they would be identical twins. As you know identical twins must be the same sex.