Endangered Species
All living organisms depend for their survival on their range of genetic variability.
Early evolution favours increasing complexity but, as a result, the organism becomes progressively more vulnerable to threats. Eventually the genetic variability range is unable to cope, the organism becomes endangered, and finally extinct.
This process has happened many times in geological history. The larger dinosaurs, which existed over a period of over 135 million years from the Jurassic to the Cretaceous, became extinct after they became too large for their territory and for their ability to move – possibly assisted by the arrival of an asteroid. Their smaller cousins who survived were the ancestors of our birds.
Much effort is currently being exerted to prevent or reverse the process of decline of supposedly “endangered species”. One strategy is to provide more living space. This seems to have succeeded, at least for a while, in African wildlife parks where human predators are causing the evolution of elephants without tusks.
The strategy has been less successful in the USA, where the available territory is more limited. A recent article in “Time” magazine shows how many smaller communities in the USA are now threatened with black bears, wolves, cougars. wild pigs, alligators and even bald eagles, who sometimes eat pets and attack children. There are now foxes on the White House lawn. The extra creatures can only find food from human dwellings.
By comparison with the mid 1900s, the population of raccoons has gone up 2.700{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, beaver 2.400{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, cougar 1,600{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117} wild turkey 1,500{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, deer 800{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, gray wolf 610{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, alligator 400{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, Canada goose 370{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, black bear 320{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}, wild pig 120{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}.
Walt Disney once made a cartoon called “Bambi” intended to help save the White Tailed Deer which is now so plentiful that it is invading people’s living rooms. There is a revival of the need for hunting bears and pigs.
In New Zealand where there were no animals, the Zealandia wildlife sanctuary has produced Kakas which are destroying the trees in the Wellington botanic gardens and filled our gardens with tuis who have displaced other native and introduced birds.
The strategy of removing predators is helpful but it cannot so easily remove recent generations of bacteria, viruses, fungi, and insects which may have been the real causes of organism decline.
The strategy of inbreeding, for which there may be little alternative, is even more likely to guarantee extinction. In my copy of a biography of King Edward 7th there is a picture of Queen Victoria and her family of over 100 people, including most of the crowned Heads of Europe. It was assumed that since they were all related, peace in Europe could be guaranteed.
It did not turn out that way. Victoria succeeded in spreading her haemophilia gene so successfully that it played a major role in the overthrow of many monarchies.
A recent History Channel documentary about dogs showed that pure breeds are usually obtained by brother/sister and mother/son matings. As a result, the prizes currently awarded at dog shows seem to go to animals barely capable of moving, let alone living very long.
The Nazi holocaust undoubtedly reduced the future genetic variability of Jewish people and this has caused a problem for contemporary Jewish communities. A recent news item from extreme orthodox Jews in Antwerp reported that they must now have a genetic clearance approval before they may marry or reproduce.
For many “endangered species” there is little alternative but to use genes that have remained, so the creatures often show the signs of inbreeding. In my recent visit to the zoo in Wellington I found that the place I enjoyed with my children and grandchildren for entertainment and instruction has become a combination of mental asylum and hospice for the animals and birds. The largest building is the hospital.
Western countries are in population decline because women are encouraged to compete for highly paid male jobs. The birth-rate has fallen below replacement level. Marriage is delayed, raising the frequency of gene damage. A depleted younger population is accompanied with a larger aged one – and the necessity for immigrants to fill the gaps. The poorest adults are solo mothers. In China the one child policy, plus a preference for boys, has led to a fall in the abundant labour which stimulated their recent progress. Meanwhile policies of “Save the Children” with no concern for their future employment, in Africa and parts of India, have led to the desperate invasion of Europe of those who have been “saved”.
Professor Steve Jones in a recent interview with Kim Hill expressed the view that the human race will become extinct because of its eventual decline in genetic variability. We are all members of an endangered species.
Have a good Christmas.
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