Prokaryotes to Eukaryotes
Today we are explaining how eukaryotes evolved from prokaryotes. We are discussing this with someone that thinks the orchard of life is a better explanation for the diversity of life than evolution. He cannot even define what species were part of the orchard but still asserts that its a better explanation.
The Best Hypothesis
The best hypothesis for how prokaryotes evolved into eukaryotes is the endosymbiosis hypothesis. Prokaryotic cells absorbed another type of prokaryotic cell which then became mitochondria. Mitochondria show all the trademarks of another prokaryotic cell and we have observed endosymbiosis happen in the laboratory.
Endosymbiosis starts with two independent prokaryotic bacteria. Then one bacteria will absorb the other but instead of being consumed the absorbed bacteria works symbiotically with its host cell. The symbiotic relationship continues between generations and now the absorbed bacteria is now part of that organism with its DNA being passed as part of the parent’s DNA.
Endosymbiosis was first hypothesized in the 1960s by Biologist Lynn Margulis. In 1966, microbiologist Kwang Jeon was observing some amoebae when they were struck with a plague of bacteria. A lot of the amoebae died as a result. Some of the amoebae did survive, though. Some time later, Jeon observed that the surviving group of amoebae were thriving with the bacteria inside the amoebae. They had attempted to kill off the bacteria inside the amoebae.This caused the host amoebae to die as well. They formed a symbiotic relationship where they couldn’t survive without each other. This is what most likely happened with prokaryotic cells when they evolved into eukaryotic cells.