Thursday’s blog made me wonder whether the coincidental and convergent evolution hypotheses agree with or contradict each other. I’ve written several blogs about convergent evolution (ie, 2018, 2020-2, 2020-3, 2020-4). My initial gut feeling is that both hypotheses do not contradict and may even agree. Let’s elaborate.
The dominant species in evolution are bacteria. Britannica encyclopedia: “ and there are convincing arguments that bacteria have been present since early Precambrian time, about 3.5 billion years ago.” Viruses, however, are a mystery, both in ageing and in origin. Nature: “To date, no clear explanation for the origin(s) of viruses exists.”
I’m inclined to believe astrobiologists Chandra Wickramasinghe and Fred Hoyle who claim that viruses might (!) be older than planet Earth itself and thus be extraterrestrial. The mere fact that viruses can survive thousands of years in ice, and be “alive” the moment they “notice” a host, suggests to me that viruses may travel (eg, asteroids) through the universe “looking” for (microbial) life (eg, bacteria).
Perhaps a farfetched idea: let’s suppose that viruses carry a “blueprint” of “evolution”. In such a case, there is nothing coincidental in evolution; everything is convergent.
The timeline of the Universe would facilitate using carriers (eg, viruses) with an “evolution blueprint”:
– age of the Universe: about 13.8 billion years;
– age of the Milky Way: about 13.2 billion years;
– age of our solar system: about 4.568 billion years;
– age of planet Earth: about 4.54 billion years;
– earliest known lifeforms on Earth: “at least 3.77 billion years ago”; possibly even 4.41 billion years ago;
– age of Homo species: “originating between two and three million years ago”. Bold markings by LO.
While planets may seem like evolutionary lab experiments (my 2019 blogs: one, two, three, four), the development of Life itself is not. Life seems predestined as if a “blueprint” is available. Neuroscientist Leonid Moroz displays similar views in a 2017 Aeon article, with this intriguing subtitle: “The ctenophore’s brain suggests that, if evolution began again, intelligence would re-emerge because nature repeats itself”.
Nature-2002: “Evolution has had at least 20 separate attempts at forming multicellular organisms. Plants, animals and fungi are the most spectacular and complex achievements of this kind.” Twenty plus attempts rules out coincidental evolution and must be convergent evolution. In other words: it’s either a blueprint or “insanity”. The only remaining question appears to be: Why does Life have a blueprint?
Calling Occupants Of Interplanetary Craft (1976) by The Carpenters (1977 cover)
Note: the 1976 original version is by the Canadian rock band Klaatu
artists, artists, lyrics, video, Wiki-1, Wiki-2, Wiki-3
Note: all markings (bold, italic, underlining) by LO unless stated otherwise