Anacondas and Evolution
There are a lot of snakes on the endangered species list (see http://www.iucnredlist.org ) but the only species of Anaconda is the dark spotted anaconda (Eunectes deschauenseei) which is not on the red list. The red list are the plant and animal species considered to face imminent extinction. Many of the snakes on the list are sea snakes which are some of the most venomous snakes on the planet. We humans have a sentient response to snakes. That means in general we react with fear at the sight of snakes.
I do not like killing anything, but a few years back there was snake outside near my garage door. My daughter saw it when she left for school and told me about it. I went downstairs to look, but it was gone. An hour later it dawned me that maybe it snuck in the garage when she left. I went to the garage and looked around. There he was curled up in a corner of the garage. I got a rake and picked him up. I took him out side and went down the driveway to put him in the bushes. He was either a brown gopher snake or a brown rattle snake. I wasn't sure and I wasn't looking too close anyway. I just wanted him to go away. Then something happened that I did not expect. He turned his head and flicked his forked tongue staring at me. At that moment I realized he did not like me, he was not grateful I moved him out of my garage, and if he had the chance he would bite me. I just knew he would come back and sneak in the garage. All of my love and passive tendencies disappeared in a flash. I went back to the garage and got a flat head shovel. When I returned he was ready to attack me, so I chopped his head off. I never felt an ounce of guilt, because I knew he wanted to bite me at some point in time. He was a rattlesnake.
I read Charles Darwin's, "On the Origin of the Species", when I was 10 years old. It was not an easy book for me to read at that age, but it was summer and I was bored. Back in those days we did not have video games and my parents restricted our TV viewing, so the local library was our entertainment. When I checked it out the librarian smiled at me. It was a very thick book. The only reason I checked it out in the first place was because I had read all of the, "Hardy Boy's" books and I wanted an adult book that would take me longer than a few days to read. I had to use our family dictionary quite often as I read because there were tons of words I didn't know.
Charles Robert Darwin, was an English naturalist, geologist and biologist, best known for his contributions to the science of evolution. He established that all species of life have descended over time from common ancestors, and in a joint publication with Alfred Russel Wallace introduced his scientific theory that this branching pattern of evolution resulted from a process that he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding. In other words, the strong survive or as with domesticated plants and animals we have selected the breeds we humans have decided to survive for our companionship, labor or consumption. As some like to say, the Law of jungle is what drives evolution. It is survival of the fittest.
Ironically many God fearing people do not believe in evolution, and many flaming liberals do, yet it is the flaming liberals that will never embrace the idea that, "The Strong Survive." That would just not fall into the ideology of group equality. In nature and the jungle, equality is not evident. Like all animals including humans, there are two choices when you face a threat; flee or fight. "Love Thy Enemy" and "Love Conquers All" or as some say with Donald J. Trump as President, "Love Trumps Hate" are flowery nice sayings void of reality. When Islamist's raise their children to hate anyone not of their faith that is basically the same as selective breeding.
The age old debate of, "Nature versus Nurture", which ironically, was debated in regards to sexual orientation during the gay rights movement, was clarified years ago in behavioral science as being both. Gays of course pushed any study or article they could find to convince society that they were born gay, even going to the extent to try and prove there was a gay gene. But, to date, no gay gene has been identified. Behaviors are both learned and inherited. Which has more influence can only be defined in specific cases and generalized opinions often just cause controversy. For example those of African and Eastern European heritage in general have a higher percentage of fast twitch muscles. In general this gives them an advantage in most sports. Rarely will you ever hear that fact outside of science because it would be considered a socially improper statement.
Anacondas are of the genus Eunectes. They are large snake found in tropical regions of South America. Currently there are four species we have been discovered and recognized. The specie most of us hear of from television and movies is the green anaconda which is the heaviest snake we know of and the second longest. Green anacondas are not on any endangered species list. They are not a venomous snake. They kill by wrapping themselves around their prey and constricting the blood flow. The females are larger than the males by a few feet or so. Females can grow up to 17 feet long. There are reports of anacondas up to 30 feet long, but those reports have never been verified. Anacondas are also a very thick snake. They spend much of their time in water and they are very good swimmers. Their eyes are set high on their head so they can stalk prey while they are in water. Not far from my home in Brazil is a small city famous for surfing. A few years back a large anaconda drifted down stream and was found near the mouth of the river. You can see the link to the video below. Anacondas are one of the few species that do not lay eggs. The offspring are ready to hunt when born. Rarely do they eat their young but females quite often eat the males after they mate.
When I was last in Brazil, in February 2017, I had a talk with the head of Agriculture sciences for the state of Bahia. Bahia is in the Pacific rainforest area of Brazil and fairly close to the Amazon basin. We were talking about anacondas and he emphatically stated that many anacondas were discovered larger than the largest ones recorded. He then said something I found both incredible and very interesting. He said anacondas were quickly evolving by natural selection into a larger snake. Now, I know from my studies of evolution that it takes more than a few generations for selective traits to evolve. I also know that traits evolve in response to environmental conditions. Also we know from the debate over nature and nurture that behaviors are both instinctive and learned. So, as I listened to his explanation as to why anacondas were evolving into larger snakes, after initial doubts, I ended up tending to believe him. It may be many decades or more into the future before the facts are verified, if at all, but the theory makes a lot of sense.
The two factors he explained both had to do with mans influence on the snakes. The first was that because more and more people have settled into remote areas and over hunted a lot of the wild animals that anacondas feast on, the larger anacondas are the ones to survive the competition for game. The second reason was because man has cleared areas for farming and domestic animals, the anacondas have found themselves forced to kill domestic animals, like sheep, pigs, goats and cows as a source of food. The larger snakes with bigger jaws are being selectively bred because of that environmental factor. Anacondas are very much night stalkers and it is very rare that humans encounter them. People on rural farms just take it as a given that if any of their domestic animals wander off at night, they most likely are not coming back. The Pacific rainforest and the Amazon basin are constantly wet and many areas are flooded during rainy season so the anacondas can travel right up to small farms. They are very fast swimmers. Anacondas in nature are at the top of the food chain, their only enemy is man and men do not go out at night to hunt them. Actually in most parts of South America the anacondas are left alone and almost viewed as a sacred animal, most likely just because hunting them is nearly impossible.
Evolution is an interesting field of study because it is dynamic. We can look into the past and study how species of plants and animals evolve. As for the future, we can only speculate how species will continue to evolve and thrive or eventually become extinct. Because the vast majority (estimated at well over 98%) of species on earth have gone extinct and it is estimated the majority of species on average go extinct within 50,000 years, there is no guarantee the human animal will be any different. Just as the saying goes, "You can take the girl out of country but you can never take the country out of the girl", I highly doubt we can ever take the Law of Jungle, out of our human societies. We we always need law and order or we will revert to our instincts. Selective breeding for humans may meld into some form of humans and robot combinations in the future, but I doubt most of the anacondas will ever give it a second thought!
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