The numbers used in this caption are up for debate. A trillion galaxies within the observable universe (which could, and, according to some theories, should just be a tiny fraction of the total universe) is well within current estimates, but there are also estimates of 100 billion or 10 trillion galaxies; likewise, the average number of stars in a galaxy might also be 100 billion instead of a trillion.
By now, it's well established that most stars have at least one planet, and a whole system of several planets seems to be the norm.
The number with the greatest uncertainty is the number of species on Earth. In the case of asexually reproducing organisms, it's not even clear what, exactly, constitutes a species. An estimate from 2014 puts the number of eukaryotic species in the vicinity of 10 millions, plus a few prokaryotes. The far more spectacular number of a trillion is taken from paper from 2016, Scaling laws predict global microbial diversity. The number of large critters we actually care about (like spiders, sharks or tapeworms or potatoes, moss or lichen or yeast) is of course expected to be much lower.
Not mentioned in the caption, but also kind of relevant is the number of inhabited planets within the observable universe. Currently, we know that the number is ≥ 1. And the number of planets with intelligent life is known to be ≥ 0.
Also worth mentioning: while most Christian sects have put heavy restrictions and regulations on admissible sexual behaviors, pretty much nobody cared about masturbation until the nineteenth century, when masturbation was mostly reframed as a medical problem.
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