What happens during gametic isolation?

During gametic isolation, fertilization fails between gametes from different species. This occurs when the sperm of one species cannot successfully fertilize the egg of another species despite the fact that they might come into contact. This mechanism of reproductive isolation ensures that even if organisms from different species attempt to mate, the union of their gametes does not lead to the formation of a zygote. Gametic isolation is particularly important in maintaining species boundaries, as it prevents the mixing of distinct genetic lineages.

The other choices do not accurately describe the process of gametic isolation. Hybrid embryos developing normally would indicate that fertilization succeeded, which is contrary to the definition of gametic isolation. If species interbreed successfully, it implies that they can produce viable offspring, again conflicting with the concept of gametic isolation. Lastly, if offspring survive to maturity, it suggests that fertilization and subsequent development occurred, which is not the situation described in gametic isolation.