“Eukaryotic Mystery “Eukaryotic Mystery“From people to protozoans, millions of organisms are made of eukaryotic cells. Eukaryotic cells are powered by mitochondria, wrap their DNA in a nuclear membrane, and have many intracellular organelles. Evolutionary scientists believe eukaryotic cells evolved from prokaryotes—single-celled organisms without nuclei, mitochondria, or other organelles. They confidently believe this despite distinctive differences and the unbridgeable chasm in their complexity. Evolutionists have however long debated which prokaryotes evolved into us. The team that discovered Lokiarchaeota notes, “The origin of the eukaryotic cell remains one of the most contentious puzzles in modern biology.”
There are two sorts of prokaryotes: bacteria and archaea. Like bacteria, archaea lack nuclei and intracellular organelles such as mitochondria. Both have circular DNA, and neither processes information in the same way as eukaryotic cells. Initially thought to be bacteria, archaea are genetically different enough to be considered a separate group of prokaryotes. There are two sorts of prokaryotes: bacteria and archaea. Like bacteria, archaea lack nuclei and intracellular organelles such as mitochondria. Both have circular DNA, and neither processes information in the same way as eukaryotic cells. Initially thought to be bacteria, archaea are genetically different enough to be considered a separate group of prokaryotes.
“Archaeans endure some of the harshest conditions on earth, including extreme temperatures. However, like some bacteria they are difficult to identify and culture in the laboratory. Many microbes, including some that secretly share our world and our bodies, have only been identified from a study of their genetic fragments—they have never been grown in a culture dish to be studied in detail. Likewise, our newest putative cousin Loki is known only from genomes pieced together by computer. Scientists reconstructed one nearly complete plausible genome and two partial ones from genetic material isolated from the mud in core samples. “Archaeans endure some of the harshest conditions on earth, including extreme temperatures. However, like some bacteria they are difficult to identify and culture in the laboratory. Many microbes, including some that secretly share our world and our bodies, have only been identified from a study of their genetic fragments—they have never been grown in a culture dish to be studied in detail. Likewise, our newest putative cousin Loki is known only from genomes pieced together by computer. Scientists reconstructed one nearly complete plausible genome and two partial ones from genetic material isolated from the mud in core samples.
“Cousin Loki? “Cousin Loki?“When we started to have a more in-depth look at the genes of this new Loki genome, we found that something was strange about it quite early on,” says lead investigator Thijs Ettema of Sweden’s Uppsala University, describing the team’s observations. Although Lokiarchaeota lack eukaryotic essentials like mitochondria, Ettema’s team “found genes that were much more like eukaryotes” and confirmed by observing their linkage to other uniquely archaean genes that they were not eukaryotic contaminants.
“Cousin Loki? “Cousin Loki?“When we started to have a more in-depth look at the genes of this new Loki genome, we found that something was strange about it quite early on,” says lead investigator Thijs Ettema of Sweden’s Uppsala University, describing the team’s observations. Although Lokiarchaeota lack eukaryotic essentials like mitochondria, Ettema’s team “found genes that were much more like eukaryotes” and confirmed by observing their linkage to other uniquely archaean genes that they were not eukaryotic contaminants.
“Veering from observations into the realm of worldview-based evolutionary conclusions, Ettema explains, “The implication is that these genomic tools were present in the lost [sic] common ancestor, and it had this genomic starter kit that helped eukaryotes become complex. Some 2 billion years ago, we took a right turn, and Loki's ancestors took a left. Loki remained in these sediments, and it never made it into a complex organism. Instead it specialized in living in these deeply buried sediments.”3 Evolutionists think such common designs are necessarily the result of either common ancestry or convergent evolution rather than a Common Designer. Accordingly Ettema adds, “We'd like to obtain more genomes of more distant cousins, and some of those might actually be closer to us or to the common ancestor than Loki is. We could maybe start to get gradual buildup, to build a road map of the journey from single-celled life towards cellular complexity.” “Veering from observations into the realm of worldview-based evolutionary conclusions, Ettema explains, “The implication is that these genomic tools were present in the lost [sic] common ancestor, and it had this genomic starter kit that helped eukaryotes become complex. Some 2 billion years ago, we took a right turn, and Loki's ancestors took a left. Loki remained in these sediments, and it never made it into a complex organism. Instead it specialized in living in these deeply buried sediments.”3 Evolutionists think such common designs are necessarily the result of either common ancestry or convergent evolution rather than a Common Designer. Accordingly Ettema adds, “We'd like to obtain more genomes of more distant cousins, and some of those might actually be closer to us or to the common ancestor than Loki is. We could maybe start to get gradual buildup, to build a road map of the journey from single-celled life towards cellular complexity.”
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