A more nuanced version of the rare earth hypothesis

The tweaked version of the rare earth hypothesis I present is this: We all know that the odds of life existing elsewhere in the universe is greater than ever before, and it is conceivable, perhaps even likely, that life can be found pretty much anywhere where there is a terrestrial body with liquid water present on it in some way (note: I`m restricting the notion of “life” to carbon and water based life like that found here on earth for obvious reasons), such as the moons of the outer solar system, perhaps even rogue planetary bodies or rogue moons as well, assuming they had oceans of liquid water present in their subsurface regions.

But I find it likely that while life may indeed be common in the universe, most of that life is going to be microbial, even on earth-like terrestrial planets orbiting stars not too different from our own. Look at it this way, for pretty much most of the history of life on earth (three and a half billion years, from the Hadean to the late Proterozoic), *all* of the biosphere was comprised of microbes, even today most of the biomass is again made up of microbes, multicellular eukaryotes make up a pithy fraction of the rest.

In the absence of necessary selective factors that are a prerequisite for multicellularity to arise in previously unicellular organisms, it can be assumed that the vast majority of life in the universe is microbial. There are about 10 or so billion earth like planets in our galaxy alone, and I’d wager that the number of those planets containing complex life on them is low, if we assume life is found everywhere where it can develop, then pretty much *all* of those planets would have life on them in some way, albeit being *microbial* life, so, using my generous assumption, there’d probably be a few hundred thousand to a few million planets with complex, multicellular life on them, that may seem like a big number but we’re dealing with 10 *billion* earth like planets out there, that’s a *pathetic* number indeed in comparison to ten *billion*.

Now how many years did it take for sapience to arise on earth (“sapience” in this context meaning “human-level intelligence,” obviously other animals are sapient as well but they probably *aren’t* human-level sapients, your pet cat or dog, while hardly idiots, don’t count, and for the sake of argument neither do dolphins or elephants)? It took roughly four billion years for the first members of the genus Homo to arise, for most of which our history we were nothing but hunter-gatherers, we’ve only been practicing agriculture for a mere ten millennia, we’ve only been recording history for about half of that, and we have only had an advanced technological civilization capable of radio astronomy for about a century now.

I think it obvious that the number of those planets with complex life on them *also* bearing sapient life at the same time we do to be *ridiculously* low, possibly even in the single digits, and most of those planets with sapient life on them odds are the sapients never left their stone age, because the development of civilization here on earth was dependent upon a number of *highly specific* circumstances that are probably, given how long we went without even developing agriculture, not that common among sapients, it was never a given *we* would develop civilization, and it is hardly a given *they* will either.

So assuming what I wrote above is true, the Fermi Paradox is hardly a paradox at all, everyone else as intelligent as we are are still stuck in the stone age and therefore have no hopes of becoming a spacefaring civilization, we’re the lucky ones, and I hope we live long enough to make us of our lucky status before climate change does us in.

Life on Venus

https://www.youtube.com/watch?v=hnGwblw54z8

Some compelling content from Mr John Michael Godier, this time he covers “10 Unsettling Solar System Possibilities.” Personally the one I found the most compelling concerned the possibility of life in the atmosphere of Venus, which I will elaborate on below:

It is known for a fact that Venus once had liquid water on its surface, like how Mars used to and how Earth currently does, and it is a fact that Venus has long since lost that water, with the surface of Venus now being a “hellish, heated wasteland” unsuitable for life. But in the atmosphere of Venus there exists a place suitable enough for extremophiles to exist, being at roughly the same atmospheric pressure as the surface of the Earth currently is.

It is possible that some life survived to call this portion of the Venusian atmosphere home, after all, microbes have been found living high up in the atmosphere of Earth as well, what’s to prevent some extremophiles from living in the atmosphere of Venus?

And as the old saying goes, life always finds a way. I once brought up an argument based off of simple thermodynamics that abiogenesis is inevitable.[1] So even though we don’t know for certain that life developed on Venus, this argument further bolsters my case.

We may have even detected possible evidence of microbial life in the atmosphere of Venus, when NASA was undergoing its usual scanning of Venus they detected small blots wherein UV was prevented from reaching the surface of Venus, and UV-absorbing microbes have been offered up as a possible explanation for this anomaly, and would also explain where these hypothetical microbes get their food, they metabolize UV radiation as an energy source.

[1] For a link to the cited paper proposing that argument in question, seeĀ here.

Why Racialism is Bullshit

https://rationalwiki.org/wiki/Racialism

The above website hosts an excellent article on why human races don’t
have a biological basis, namely stating that “human population diversity
is too subtle to be placed in arbitrary geographic groupings, or
‘races'”. For example, in China the farther north you get the more
shoveled the people’s teeth become, whereas the farther south you get
the less shoveled the people’s teeth becomes. Africa also has the
world’s highest genetic diversity, which is something we’d expect if the
Out of Africa hypothesis was true, and that is what we find. Indeed, if
we use genetics as a basis for “race” West and East Africans would be
completely separate races.

Instead of race we should focus more on ethnicity, or clines, which
better fit human population diversity. Examples of clines including the
Irish, the San Bushmen, and Fijians. There’s a reason Africa is home to
the most genetically diverse people on the planet, and it ain’t because
of Adam and Eve.

This is not to say that there aren’t any genuine differences between the various human populations, there are, but the concept of there being distinct “races” within our species doesn’t cut it, it’s bullshit, and in fact is an impediment to better understanding of the evolutionary history and population biology of our own species, Homo sapiens.

An even better model to use when modeling human populations is the concept of the demes, or “breeding population”. A standard breeding population is around 25,000 people, in which people are more likely to breed within their demes than without, a good example of a demes today would be the Amish. An ethnic group such as the Han Chinese aren’t a demes, they consist of one billion people and have multiple demes within their ethnic group.

Explaining homology

Homology is the study of shared features between taxonomic clades, such as how all tetrapods, from amphibians to mammals, possess fingers, and is something that can only be explained by evolution. For example, what intelligent designer would give whales fingers and leg bones enveloped inside of a fleshy membrane, complete with shoulders, instead of giving them fish fins, and what intelligent designer would give whales lungs instead of enabling them to filter oxygen through the water like fish do?

These are the hallmarks of evolution, not creation. Evolution explains homology, Creationism doesn’t. It is as the late, and great, eminent Ukrainian evolutionary biologist Theodosius Doubzhansky once said:

Biology only makes sense in the light of evolution.

Homology is just one of many things in modern biology that can only be explained by evolution. Homology is indicative of common descent, not common design, as some Creationists like to claim. No intelligent designer would give whales lungs, after all.

Homology as a science was first devised by the great French anatomist and paleontologist Georges Cuvier himself, widely regarded to be the “Founder of Paleontology”, and who also happened to be a creationist, albeit not a young-earth creationist, he died a quarter of a century before Darwin published his seminal masterpiece On the Origin of Species (1859).

This is the second entry of a series of essays explaining basic evolutionary biology, the first can be found here.

A Basic Definition of Evolution

There are still tons of misconceptions floating around out there about what evolution is, and what it isn’t, so I think I should take it upon myself to provide a basic, and accurate, definition of evolution consistent with what we actually know to be true about evolution.

Evolution is simply the change in the frequencies of allele variations in any given population over time. An alternate definition of evolution is that evolution is simply descent with inherent modification, and the two separate definitions aren’t mutually exclusive.

Notice that neither of those definitions have anything to do with a “kind turning into a completely different kind”, such as the infamous Crocoduck of Kirk Cameron’s imagination, nor does it have anything to do with abiogenesis, the big bang theory, planetary formation, stellar nucleosynthesis, and the like. Evolution is solely an explanation of biodiversity, that’s it.

Perhaps the reader will be confused by how abiogenesis and evolution are two completely separate phenomena, so let me explain: Abiogenesis is about how life got here, while evolution only has to do with what happens after life got started in the first place. In other words, one needs a genome to evolve, something that prebiotic organic chemicals lack.

So it’s perfectly logically and theologically consistent for one to believe in both a deity and acknowledge evolution as the sole valid explanation for biodiversity, despite what the Fundies would have you believe.

A good source for understanding basic evolutionary biology can be found in the link below:

Understanding Evolution