Stephen Juan - Can Kissing Make You Live Longer?: Body and Behaviour Mysteries Exlained Oddball Questions

(Asked by Ralph Turner of Bangor, Maine, USA)

All forms of life, from the simplest to the most complicated, are classified scientifically into a system known as taxonomy. As humans we are Homo sapienswe are animal, mammal and primate in one. According to the classic taxonomic system developed by Swedish biologist Carl Linnaeus (17071778), and added to by many others since, humans are classified into: domain, kingdom, phylum, class, order, superfamily, family, genus and species. Although some authorities dispute various aspects of what appears below and have even proposed additional categories, humans are taxonomically humans due to the following:

Domain: Eukaryota. We are classified among organisms with a complex cell or cells and with genetic material that is organised into a membrane-enclosed nucleus or nuclei.

Kingdom: Animalia. We are classified among organisms that are multi-cellular, capable of locomotion and feeding themselves via other organisms or parts of other organisms, and those that develop a stable body structure.

Phylum: Chordata. We are classified among the vertebrates (those animals with a type of spinal cord) or closely related and complicated invertebrates. Chordates have a notochord which is a flexible, rod-shaped body form in embryos. In lower vertebrates it continues throughout life. In higher vertebrates it becomes a vertebral column. Chordates have a dorsal nerve cord which later becomes the brain and spinal cord. It is formed from a part of the ectoderm that rolls and forms a hollow tube. Chordates have pharyngeal slits used for feeding. In primitive chordates the pharyngeal slits strain water and filter food particles. In more advanced chordates the pharyngeal slits disappear at the embryo stage. Chordates have an endostyle which is a groove on the ventral wall of the pharynx that produces mucus used in eating. Chordates have pharyngeal pouches which are also used for feeding. These become gills in fish. Chordates also have a tail. In our case we have only vestigial evidence of this.

Class: Mammalia. We are classified among the vertebrate animals that have: mammary glands that produce milk; hair or fur; specialised teeth; three small bones in the ear; a neocortex region in the brain; warm-blooded bodies; a four-chambered heart; and a brain-regulated circulation and temperature-controlling system.

Order: Primate. From the Latin word primus meaning first, we are classified among the prosimians that most closely resemble the early proto-primates (such as lemurs), the monkeys of the New World (such as capuchin monkeys), and the monkeys of the Old World (such as baboons).

Superfamily: Hominoid. We are classified among the non-human-like primates, that is, the great apeschimpanzees, gorillas and orang-utans.

Family: Hominidae. We are classified among the human-like primates both extinct and still in existence.

Genus: Homo. With the Latin homo meaning man or human in its more recent meaning, we are classified among modern humans and our close now extinct relatives. Homo erectus (upright human), Homo neanderthalis (Neanderthal human), Homo habilis (tool-making human), Homo floresiensis (flower human) and others.

Species: Sapiens. With the Latin sapiens meaning wise, we are Homo sapiens (wise humans). Some argue that Homo sapiens idaltu (elder wise humans) is of our species, too, although also now extinct; others argue that we should be rightly classified as Homo sapiens sapiens to make clear this last distinction.

(Asked by Ralph Turner of Bangor, Maine, USA)

It is anyones guess as to what will be the next step in the evolution of Homo sapiens. Nature has been working on the model for more than 3 million years through natural selection. Some scientists have speculated that the next adaptive changes to humans may be to the anatomical structure with better spine, ears, eyes, hips, joints, etc. or perhaps it will be changes in our brain or in our consciousness that will usher in the next subspecies. Homo sapiens humanus (as opposed to Homo sapiens non-humanus) would be a modern human who is humane, cultured, refined, educated, compassionate, empathetic, creative, intuitive, courageous, spiritual, generous and energetic. (An ideal dinner party guest?) They would be teachers, healers, helpers, creators, preparers, nurturers, transformers and repairers. (Pretty handy to have around, right?) They would see something and want to make it better, and think of others not just of themselves. They would understand the most important philosophical principle of human awareness: that the greatest receiving comes from the greatest giving. Our body, brain and consciousness would evolve together. For example, we now know that experience during the early years of human development has effects on brain structure, particularly in the frontal lobe region responsible for empathy. This in turn affects changes in human behaviour. Those receiving a humanus experience will develop more advanced brains than those receiving a non-humanus experience. Such advancement would be passed on from offspring down to another and so on in the lineage. Perhaps through our more enlightened behaviour we could influence our own evolution?