(Un)expected Visitors 4: Human Biology Reflects Habitat
By: Paul Rommel Elvira
Tags: Human Biology, Specimen, Habitat, Earth, Directed Panspermia

Human Biology Reflects Habitat

“It is not the organs — that is, the character and form of the animal’s bodily parts — that have given rise to its habits and particular structures. It is the habits and manner of life and the conditions in which its ancestors lived that have in the course of time fashioned its bodily form, its organs and qualities.”- Jean-Baptiste Lamarck

If the alien scientists are to examine the human body (with or without our permission), they are going to discover a wealth of information about our home planet. Our lungs are a dead giveaway about the presence of an atmosphere on Earth. The alien scientists can determine further the content of this atmosphere by looking at our blood. The bright red color of human blood results from oxygenation. This distinct color of blood develops when hemoglobin — a protein in red blood cells — binds oxygen.

Our digestive tract is also very revealing about the human diet, as well as the vegetation on Earth. Alien scientists can imitate how anthropologists surmise the behavior of our human ancestors. Our flat but thick-enameled molars give a hint that these were used for grinding seeds as well as for crushing marrow out of bones. The presence of different enzymes, such as amylase, in our saliva indicates the presence of starch in the food we eat. Our bone structure and even our heart’s pumping capacity can indirectly indicate the strength of gravitational force on Earth. Research has found that the human tibia can handle up to 90 times the gravity of Earth. Meanwhile, the human heart has been said to be able to tolerate up to 5gE or five times the gravity at the Earth’s surface (about 4gE in the long run) [1].

Of course, it is easy for the alien scientists to deduce that we thrive on land and not in water since we do not have gills, webbed hands or webbed feet. They would easily notice that we are bipedal; that is, if they found the human explorers alive and not dead or cryo-preserved in deep space. However, these are simple pieces of information that the aliens might gloss over because these are facts applicable only to humans and our environment. What they would probably be looking for is a bit of comprehensive but detailed look at our planet, including its history.

For example, if they are lucky enough, they could find a pregnant crew member of the human space exploration team. Using advanced equipment, the alien scientists would be able to observe the development of the human embryo inside the mother’s womb. From the different stages of human embryogenesis, the alien scientists could somehow guess how the relatives, such as other vertebrates, of humans develop. They would notice that the human embryo temporarily develops tails but only retains the coccyx unlike all other vertebrates that develop fully formed tails. The human embryo also shows gill slits that are shared with other vertebrate embryos. The gill slits of human embryos end up forming the lower jaw and Eustachian tube, however, and do not completely become gill openings such as those in fish and larval amphibians.

From these observations, alien scientists would be able to deduce the existence of distant or primitive relatives of humans having tails or gills that are useful for dangling from tree branches and breathing underwater, respectively. However, this type of analysis would require a lot of guesswork on the part of the alien scientists who presumably do not have much information to start with. Therefore, they would have to use more reliable data to get a glimpse of the evolutionary history of humans. For that, the alien scientists would have to take a closer look at our genetic material.

Since they are an advanced civilization, they would probably know about DNA, RNA or any kind of genetic material familiar to them. We can assume that alien scientists are going to zero in on genes or genomes to know more about humans as well as Earth and all the other organisms we are related to. This is not entirely surprising since they could have done it on their own species and other organisms on their own planet. They would most likely have their own tree of life and one of the branches could even lead to us! That last one is a big leap of faith but it would make sense if they indeed experimented on Earth and seeded life here. However, there is also a possibility that life on Earth could be totally different from that on their planet due to the unique geological conditions on either planet. This is inconsequential, however, and the only important part is that the alien scientists would know how to analyze our anatomy including our genetic characteristics.

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