Science can't define "species" (Talk.Origins)
Complaints about creationists not defining "kind" are unfair since evolutionists can't define "species" consistently.
First of all this is not a creationist claim, Talk Origins doesn’t even give a source.
The simple fact is that "kind" does have a definition.
Kind: A group of organisms descended from a group of common interbreedable ancestors. Note that only the ancestors have to be interbreedable.
Now there has been some difficulty in reconciling the Created kinds concept to the standard classification system, but this has largely been because the Created kinds are not a perfect fit with the classification system. Furthermore, new discoveries have caused changes in our understanding of which animals are and are not the same “kind”.
(Talk.Origins quotes in blue)
1. Species are expected often to have fuzzy and imprecise boundaries because evolution is ongoing. Some species are in the process of forming; others are recently formed and still difficult to interpret. The complexities of biology add further complications. Many pairs of species remain distinct despite a small amount of hybridization between them. Some groups are asexual or frequently produce asexual strains, so how many species to split them into becomes problematical.
Likewise “kinds” are expected sometimes to have fuzzy and imprecise boundaries because of the degree of diversification that has occurred even since the Flood. So both sides do have a similar problem.
Creation, defining things as kinds that were created once and for all, implies that all species should be clearly demarcated and that there should be a clear and universal definition of kind or species. Since there is not, creationism, not evolutionary theory, has something to explain.
- The created kinds are not the same as species.
- The created kinds have not been static but have diversified since they were created.
2. Different definitions of species serve different purposes. Species concepts are used both as taxonomic units, for identification and classification, and as theoretical concepts, for modeling and explaining. There is a great deal of overlap between the two purposes, but a definition that serves one is not necessarily the best for the other. Furthermore, there are practical considerations that call for different species criteria as well. Species definitions applied to fossils, for example, cannot be based on genetics or behavior because those traits do not fossilize.
The same thing applies to the Created kinds concept. For example, while hybridization works well for establishing living animals as the same “kind”, it does not work for fossils since they are a little hard to breed.