After a second look at the tree of life, scientists are rethinking the asexuality of amoebae, regarded as the epitome of chastity. They have now evidence of life amoeboid sex, suggesting the Act did not evolve, it has always been there.
Amoebae are creatures of type blob on an old billion years - - the oldest members of the domain of life called eukaryotes. This group is fundamentally different in appearance and other characteristics of these two other areas of life. Amoeba species are distributed throughout this tree on each branch, interspersed with familiar lines such as plants and animals. They are known for how they move, slowly extending to as parts of their cell membranes.
"It changes how to interpret the evolution of organisms," study researcher Daniel Lahr, the University of Massachusetts, told LiveScience. "If the last common ancestor of eukaryotes is sexual, then it is in practice no evolution of sex."
Taking a sweep looking at what we know about them by conducting a search through the scientific literature, researchers say that these amoebae are more sexually active that we believe.
"When we talk about the sex of amoeboid protists, existing evidence not evoke chastity, but rather of Kama Sutra," Lahr writes in the book, published in the March 23 of the journal Proceedings of the Royal Society B Biological Sciences:. [Why we sex: 237 reasons revealed]
Asexual Amoeba
Sex Amoeba would have been missed because when grown in the laboratory, many of them show no signs of engaging in sexual relations - they have the ability to reproduce by cloning, or the copy themselves indefinitely. And when they show signs of sex, researchers are wrong for a rare exception to the rule of non-sexe.
This is why most researchers believe that the amoebae (and all eukaryotes) has evolved from an asexual ancestor.
For these lower organisms sex is not so much an act between a male and a female with all the complications "birds and bees" with. Amoebae, sex is a special way to divide its genetic material in two while also divided doses, and then combines two of these packets into a new body. These two doses may come from the same person or different people.
When the genetic material is being classified off it undergoes a process and switches around some parts of its DNA. This switch gives the new individuals a greater diversity in their genes. They reproduce always using sex because in some environments, asexual reproduction can be more effective.
"The speed of Division is immediately beneficial to the individual," Lahr told LiveScience. "But in most cases, it is a condition that is doomed to extinction."
Muller ratchet
Asexuality is a game loser in the long term, because the errors accumulate in the genome and get passed on to descendants, eventually kill. This theory is called ratchet Muller and is traditionally used to explain why sex has evolved.
When genomes are mixed in the separation and the reconstitution of DNA during intercourse, the descendants can excrete these errors. Some animals asexual, such as bdelloid (small multicellular animals), have developed other ways to recombine their genomes and avoid the squeeze ratcheting of Muller.
"The message bring-home to the biology community: in General, they must examine more broadly that they would have if they really want to talk about theories on sex and gender roles,"said Fred Spiegel at the University of Arkansas".who wrote a commentary on the study for the same issue.
"The last common ancestor of all eukaryotes of life must be sexual," Spiegel told LiveScience. "Sex is the rule and not the exception."
You can follow LiveScience staff writer Jennifer Welsh on Twitter @ microbelover.
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