1. How did life originate?
For 80 years now we are told that the first self-replicating molecules appeared in the primordial soup in the Earth’s shallow waters, which happened 4 billion years ago. This “soup” was composed of amino-acids, polypeptides, and nitrogenous bases of nucleotides formed as a result of electrical charges, high heat and cosmic radiation.
However, the experiments to replicate similar processes have given mixed results: the basic monomers began to form substances that prevented the expected complexity to exist in this “soup” of polymers.
Later, the problem seemed to have been simplified by the “RNA world” hypothesis, but the probability of spontaneous formation of RNA, which wouldpossess catalytic properties, is very low. It is estimated that four billion years are not enough. It is difficult to envision that we are incorrect in our assumptions about Earth’s conditions back in the time (thanks to geologists and paleontologists). In general, how RNA emerged and what it gave rise to still remains a mystery. It even boils down to assumptions by some authors when they move our ancestral home to Mars, where the conditions for RNA formation were much more favorable!
2. What makes us human?
Some of us have a big brain, but elephants and whales have even bigger brains. Some of us know how to make tools, but, as it turned out to be, parrots, seals and other animals are capable of doing this also. Granted, tools are systematically created by, for example, apes, but they do not become more evolved during this process. Perhaps fire? Chimpanzees are quite quick to learn how to start a fire with a lighter, or a match, but have not yet shown the level of intelligence qualifying them for a membership in the UN. Language? However, if not the language, but pictograms were readily available to apes of different species, and they are even able to communicate on a local network with an invisible “companion”, including both people and their own species. Social culture? Unlikely. Orangutans after migrating to a new habitat seem to learn from other groups about hunting techniques, eating habits, and other elements of behavior, including regional variations of sound signals…
So what is the thing that separates us from them?
3. Will we ever be able to conquer death?
That is, do we have the ability to live indefinitely, right? The short answer is no, if you are a multi-cellular organism. But this answer is suspiciously short…
In fact, some of multi-cellular organisms are essentially immortal unless, of course, they are subjected to complete annihilation. Perhaps their aging is so slow that scientists cannot record the moment of their death due to natural causes (“negligible senescence”). Medusa Turrilopsis nutricula, sea anemones, and Hydra will certainly not die due to aging, they need to be affected by external factors to cease their existence.
Apparently, the Mountain bristlecone pine, appears very similar to these organisms, its oldest known species dates back 5 thousand years, given the tree is defenseless against being cut, fires and lightning, we can assume that this species can only die because of these deadly events. In the recent years it became known that clam species Arctica islandica can reach an age of 500 years with no visible changes in morphology. Similar patterns are observed in turtle Terrapene carolina, sea urchin Strongylocentrotus franciscanus, redfish Sebastes aleutianus, etc. All of the captured oldest-living species do not show signs of aging, such as reduced fertility, etc. Nothing would set them apart from species which are a hundred years younger. Finally, the species of sponge Scolymastra joubini is estimated to live up to 23 thousand years!
Perhaps, elusive species with slow aging are far more numerous than it is known to biologists. Specifically, the age of the lobster species is impossible to determine, but the age-related changes after they mature are still absent. Obviously, studying the mechanisms of this longevity could help solve aging problems in humans, although it is hard to predict to what extent or how.
4. What is consciousness?
Maybe the answer is “consciousness”? But this answer does not help: we still have no idea what it is. Presumably, consciousness is formed physiologically by the interaction (possibly network-like) of different regions of the brain. The catch is that we cannot monopolize our brain, and it is unclear why the reflexes and self-awareness should be limited only by us…
5. What is the purpose of sleeping?
Even when we are asleep, the brain still functions all the time, right? What kind of rest is this when there is no resting? And how come some vertebrates sleep with only one hemisphere of the brain? Why spend a third of your life on the process, the purpose of which is unclear…?
There is, of course, a theory that sleeping helps our learning, when during this process, we “reboot the brain”, allowing the synapses to “upload” memories into the long-term memory, otherwise after a while the number of accumulated memories would be too big and new memories could not be formed, which would cause significant damage to our consciousness. But frankly speaking, it is still a suggested hypothesis, although it is gaining some recognition.