A group of Tel Aviv University researchers at the Proceedings of the National Academy of Sciences (PNAS), USA has published a journal that confirms the existence of a multicellular eukaryotic organism that is a myxozoan relative of jellyfish and corals and does not need oxygen to survive. Henneguya salminicola, a 10-celled tiny parasite, lacks the Mitochondrial DNA and thus doesn’t have the ability to perform aerobic respiration.
Crux of the Matter
What is a Parasite? Parasites are plants or animals that live on or in a host getting their nutrients from that host. A host is an organism that supports a parasite. Sometimes the host is harmed by the parasite, and sometimes the relationship is neutral. But the host never benefits from the arrangement. When the parasite does have a negative impact on the host, it doesn’t often kill the host directly, but the stressors that come with having parasites can kill.
To “Air” May be Human, But Not for This Parasite In the paper, the authors, Dayana Yahalomi of Tel Aviv University and Stephen D. Atkinson of Oregon State University used deep sequencing approach to investigate why H. salminicola doesn’t perform aerobic cellular respiration. The output was an absence of any mitochondrial DNA, which also indicated that core eukaryotic features are not omnipresent among animals.
According to the research, H. salminicola evolved to become less complex as opposed to the general acceptance of evolution giving rise to elaborate structures and mechanisms in organisms. The transition occurred over time, to ensure that it survives in its anaerobic environment i.e inside of salmon fish muscles. The genomic results further stated that it gave up breathing and consuming oxygen to produce energy.
Can Evolution Go in Strange Directions? Organisms like fungi, amoebas or ciliate lineages do lose the ability to breathe over time. But animals are multicellular, highly developed organisms that first appeared on Earth when oxygen levels rose.
Prof. Huchon, a professor onboard, says “It’s not yet clear to us completely how the parasite generates energy as of now. We just know how this discovery bears an enormous significance for evolutionary research.” This finding can resurface the debate amongst biologists, regarding the possibility of survival of organisms belonging to the animal kingdom, in anaerobic environments.
“Mitochondria are the powerhouses of the cell?” Not for this creature. https://t.co/WMJ6hJt5c2 — NYT National News (@NYTNational) February 29, 2020
Curiopedia
Evolution of biological complexity is one important outcome of the process of evolving. Evolution has produced some remarkably complex organisms, with properties such as gene content, the number of cell types or morphology all proposed as possible metrics. The actual level of complexity is still very hard to define or measure accurately in biology,
Many biologists used to believe that evolution was progressive via orthogenesis. This idea of “progression” and “higher organisms” in evolution is now regarded as misleading, with natural selection having no intrinsic direction and organisms selected for either increased or decreased complexity in response to local environmental conditions. Although there has been an increase in the maximum level of complexity over the history of life, there has always been a large majority of small and simple organisms and the most common level of complexity appears to have remained relatively constant. More Info
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