[ahayes]

Just wondering, what is the simplest life form that is able to be linked to the chain of evolution thus far?

The prokaryotes (single-celled organisms without membrane-bound organelles), kingdoms Eubacteria and Archaea. These at one point had a common ancestor but it is lost. Eukaryotes (organisms with membrane-bound organelles) are thought to have evolved through some type of symbiotic arrangement between bacteria and archaebacteria. The simplest version involves an archaebacterium engulfing an bacterium, the bacterium lives inside the host and provides oxygen scavenging, hydrogen, or some other benefit. Over time many genes on the engulfed bacterium's genome become transferred to the nucleus (there are varying theories about how that arose too), new genes arise, and eventually we get the modern eukaryotes with mitochondria.

Support for this idea includes the fact that eukaryotes like us share many metabolic enzymes with bacteria, but our mechanisms for gene transcription and translation are more like the archaebacteria's.

[furball4paws]

Also the similarity of of some of our mitochondrial genes with those of procaryotes.

[Old_Mil]

The prokaryotes (single-celled organisms without membrane-bound organelles), kingdoms Eubacteria and Archaea. These at one point had a common ancestor but it is lost. Eukaryotes (organisms with membrane-bound organelles) are thought to have evolved through some type of symbiotic arrangement between bacteria and archaebacteria. The simplest version involves an archaebacterium engulfing an bacterium, the bacterium lives inside the host and provides oxygen scavenging, hydrogen, or some other benefit. Over time many genes on the engulfed bacterium's genome become transferred to the nucleus (there are varying theories about how that arose too), new genes arise, and eventually we get the modern eukaryotes with mitochondria.

Support for this idea includes the fact that eukaryotes like us share many metabolic enzymes with bacteria, but our mechanisms for gene transcription and translation are more like the archaebacteria's.

Or, the obvious explanation being that all life that shares a common environment is going to have similar methods of existing within that environment. This is a prime example of the flaw in evolutionary thinking. Evolutionary biologists approach all science with one unassailable dogma: evolution is true. Thus, all the "evidence" must be forced into this framework. Since evidence does not exist (as in the above theory of endosymbiosis), the theory (which is in reality little more than science fiction) is pronounced as fact and held forth as evidence.

All statements from evolutionary biologists can be reduced to fit the following framework:

(1) A looks or functions like B
(2) We know evolution is true
(3) Therefore A and B have a common ancestor

[From many - one.]

Browsing a magazine at the airport and saw an article about a very unusual large virus that shares some markers. They called my flight, but more info should be out there somewhere. I'm off again so can't follow up.