Specialization is the Way to Extinction

Now let us examine more closely what we know scientifically about extinction. At the annual Congress of the American Association for the Advancement of Science, as held approximately ten years ago in Philadelphia, two papers were presented in widely-separated parts of the Congress. One was presented in anthropology and the other in biology, and though the two author-scientists knew nothing of each other's efforts they were closely related. The one in anthropology examined the case histories of all the known human tribes that had become extinct. The biological paper investigated the case histories of all the known biological species that had become extinct. Both scientists sought for a common cause of extinction. Both of them found a cause, and when the two papers were accidentally brought together it was discovered that the researchers had found the same causes. Extinction in both cases was the consequence of over-specialization. How does that come about?

We can develop faster and faster running horses as specialists. To do so we inbreed by mating two fast-running horses. By concentrating certain genes the probability of their dominance is increased. But in doing so we breed out or sacrifice general adaptability. Inbreeding and specialization always do away with general adaptability.

There's a major pattern of energy in universe wherein the very large events, earthquakes, and so forth, occur in any one area of universe very much less frequently than do the small energy events. Around the Earth insects occur more often than do earthquakes. In the patterning of total evolutionary events, there comes a time, once in a while, amongst the myriad of low energy events, when a large energy event transpires and is so disturbing that with their general adaptability lost, the ultra-specialized creatures perish. I will give you a typical history-that of a type of bird which lived on a special variety of micro-marine life. Flying around, these birds gradually discovered that there were certain places in which that particular marine life tended to pocket-in the marshes along certain ocean shores of certain lands. So, instead of flying aimlessly for chance finding of that marine life they went to where it was concentrated in bayside marshes. After a while, the water began to recede in the marshes, because the Earth's polar ice cap was beginning to increase. Only the birds with very long beaks could reach deeply enough in the marsh holes to get at the marine life. The unfed, short-billed birds died off. This left only the long-beakers. When the birds' inborn drive to reproduce occurred there were only other long-beakers surviving with whom to breed. This concentrated their long-beak genes. So, with continually receding waters and generation to generation inbreeding, longer and longer beaked birds were produced. The waters kept receding, and the beaks of successive generations of the birds grew bigger and bigger. The long-beakers seemed to be prospering when all at once there was a great fire in the marshes. It was discovered that because their beaks had become so heavy these birds could no longer fly. They could not escape the flames by flying out of the marsh. Waddling on their legs they were too slow to escape, and so they perished. This is typical of the way in which extinction occurs — through overspecialization.

Specialization comes at the cost of general adaptability. So when the environment changes, the highly-specialized go extinct.