- Thierry Lod?described reproductive strategies in terms of the development of the zygote and the interrelationship with the parents; there are five classifications-ovuliparity, oviparity, ovo-viviparity, histotrophic viviparity and hemotrophic viviparity.
- Viviparous fish have developed several ways of providing their offspring with nutrition . " Embryotrophic " or " histrotrophic " nutrition occurs by the production of nutritive fluid, uterine milk, by the uterine lining, which is absorbed directly by the developing embryo . " Hemotrophic " nutrition occurs through the passing of nutritive substances between blood vessels of the mother and embryo that are in close proximity, i . e . a placenta-like organ similar to that found in mammals.
- His revised modes are ovuliparity, with external fertilisation; oviparity, with internal fertilisation of large eggs containing a substantial nutritive yolk; ovo-viviparity, that is oviparity where the zygotes are retained for a time in a parent's body, but without any sort of feeding by the parent; histotrophic viviparity, where the zygotes develop in the female's oviducts, but are fed on other tissues; and hemotrophic viviparity, where the developing embryos are fed by the mother, often through a placenta.