The creation record found in the first chapter of Genesis reveals that Jehovah God created earth’s living things “according to their kinds.” (Ge 1:11, ftn) Toward the end of the sixth creative day the earth was supplied with a great variety of basic created “kinds,” which included very complex forms of life. These were endowed with the capacity for reproducing offspring “according to their kind(s)” in a fixed, orderly manner.—Ge 1:12, 21, 22, 24, 25; 1Co 14:33.
The Biblical “kinds” seem to constitute divisions of life-forms wherein each division allows for cross-fertility within its limits. If so, then the boundary between “kinds” is to be drawn at the point where fertilization ceases to occur.
In recent years, the term “species” has been applied in such a manner as to cause confusion when it is compared with the word “kind.” The basic meaning of “species” is “a sort; kind; variety.” In biologic terminology, however, it applies to any group of interfertile animals or plants mutually possessing one or more distinctive characteristics. Thus, there could be many such species or varieties within a single division of the Genesis “kinds.”
Although the Bible creation record and the physical laws implanted in created things by Jehovah God allow for great diversity within the created “kinds,” there is no support for theories maintaining that new “kinds” have been formed since the creation period. The unchangeable rule that “kinds” cannot cross is a biologic principle that has never been successfully challenged. Even with the aid of modern laboratory techniques and manipulation, no new “kinds” have been formed. Besides, the crossing of created “kinds” would interfere with God’s purpose for a separation between family groups and would destroy the individuality of the various kinds of living creatures and things. Hence, because of the distinct discontinuity apparent between the created “kinds,” each basic group stands as an isolated unit apart from other “kinds.”
From the earliest human record until now, the evidence is that dogs are still dogs, cats continue to be cats, and elephants have been and will always be elephants. Sterility continues to be the delimiting factor as to what constitutes a “kind.” This phenomenon makes possible, through the test of sterility, the determining of the boundaries of all the “kinds” in existence today. Through this natural test of fertilization it is possible to uncover the primary relationships within animal life and plant life. For example, sterility presents an impassable gulf between man and the animals. Breeding experiments have demonstrated that appearance is no criterion. Man and the chimpanzee may look somewhat similar, have comparable types of muscles and bones; yet the complete inability of man to hybridize with the ape family proves that they are two separate creations and not of the same created “kind.”
Although hybridization was once hoped to be the best means of bringing about a new “kind,” in every investigated case of hybridization the mates were always easily identified as being of the same “kind,” such as in the crossing of the horse and the donkey, both of which are members of the horse family. Except in rare instances, the mule thus produced is sterile and unable to continue the variation in a natural way. Even Charles Darwin was forced by the facts to admit: “The distinctness of specific forms and their not being blended together by innumerable transitional links, is a very obvious difficulty.” (Origin of Species, 1902, Part 2, p. 54) This still remains true.
Whereas specific created “kinds” may number only in the hundreds, there are many more varieties of animals and plants on the earth. Modern research has indicated that hundreds of thousands of different plants are members of the same family. Similarly, in the animal kingdom, there may be many varieties of cats, all belonging to one cat family or feline “kind.” The same is true of men, of cattle, and of dogs, allowing for great diversity within each “kind.” But the fact remains that no matter how many varieties occur in each family, none of these “kinds” can commingle genetically.
Geological research provides clear evidence that the fossils held to be among the earliest specimens of a certain creature are very similar to their descendants alive today. Cockroaches found among the supposed earliest fossil insects are virtually identical to modern ones. Fossil “bridges” between “kinds” are totally lacking. Horses, oak trees, eagles, elephants, walnuts, ferns, and so forth, all continue within the same “kinds” without evolving into other “kinds.” The testimony of the fossils is in full accord with the Bible’s history of creation, which shows that Jehovah created the living things of the earth in great numbers and “according to their kinds” during the final creative days.—Ge 1:20-25.
From the foregoing, it becomes apparent that Noah could get all the necessary animals into the ark for preservation through the Flood. The Bible does not say that he had to preserve alive every variety of the animals. Rather, it states: “Of the flying creatures according to their kinds and of the domestic animals according to their kinds, of all moving animals of the ground according to their kinds, two of each will go in there to you to preserve them alive.” (Ge 6:20; 7:14, 15) Jehovah God knew it was necessary to save only representative members of the different “kinds,” since they would reproduce in variety after the Flood.—See ARK No. 1.
Following the recession of the floodwaters, these comparatively few basic “kinds” emerged from the ark and spread out over the surface of the earth, eventually producing many variations of their “kinds.” Although many new varieties have come into existence since the Flood, the surviving “kinds” have remained fixed and unchanged, in harmony with the unchangeable word of Jehovah God.—Isa 55:8-11.