Earliest Catalysts of Human Evolution into an Invasive Species

folio-frugivore

This story is based on a melding of

Mike Munford’s hypothetical reconstructions based on

Cohen’s Food Crisis in Prehistory: Overpopulation & Origins of Agriculture,

Keeley’s War Before Civilization: The Myth of the Peaceful Savage,

Wrangham’s Catching Fire: How Cooking Made Us Human, and

Ernst Mayr’s work on speciation;

inspiring written and oral words of Layla AbdelRahim,

David Watts on point challenges & questions and

Sussman’s Man the Hunted: Primates, Predators & Human Evolution,

sparking the imagination of a Cascadian Forest Steward

Ria Del Montana.

Given the science that…

From origins, life has been in a transformation process of adapting to change, yet striving for and settling into a homeostasis. Life and entire ecosystems form, grow, and die through little and big, slow and fast changes. Life thrives when species slowly co-adapt with one another, striking a balance, forming an interacting community, evolving in relation, co-becoming as indigenous to an ecosystem. The resilience of the ever shifting system is particularly determined by keystone species on which much life or even the whole community critically depend. Even rare plant or animal species in the smallest niche may play a vital role in a natural area’s vigor. The introduction of any new species into an ecosystem with which indigenous life has not had time to co-adapt has the potential to become invasive, more than interrupting homeostasis, but fundamentally damaging.

When a species moves into an ecosystem, the new environment presents both challenges (e.g. finding different nourishment), and opportunities (e.g. easy spread due to fewer predators). Neither has the alien species had time to adjust to the environment and its indigenous species, nor has the indigenous species had time to adapt competent defenses to and relationships with the alien species. Abrupt change in conditions requiring abrupt adaptation to survive mostly leads to die off, but can also lead to eventual naturalization, or invasiveness.

The origin of species, speciation, is the crux of evolution. A species embodies a set of unique basic characteristics. External minor differences between individuals and gradual changes occur easily, while quintessential changes such as formation of genetic variants and subspecies are less flexible. When populations of species are divided by a physical barrier, over time genetic changes diverge based on adaptations to pressures from differing ecological, geological and climactic conditions. The most resilient adaptation can take extreme forms, for example changing from plant to animal-based diet.

Could it be, through a series of catalysts we have evolved against our original nature into an invasive predator?

When environmental changes tested early humans to adapt quickly or die, they not only adapted, but ‘overadapted’, eventually enabling us to spread by foot and boat into other ecosystems. We colonized bioregions, domesticated and hunted other species, triggering a total transformation of ecosystems and evoking an escalating series of extinction events.

Despite today’s popular ‘man the hunter’ myth, the most impartial studies are increasingly finding that all early primates including early humans were not hunters but prey of many predators, including early species of wild dogs and cats, hyenas, eagles and crocodiles. From origins, early human was not an aggressive killer, not a hunter-gatherer, but a forager living with fear as all prey.

Australopithecus afarensis from sub-Saharan Africa is commonly agreed to be the ‘link’ from ape to human. Adults ranged from around 3 to 5 feet, weighed 60-100 pounds. These small, strong, long-armed bipedal primates with relatively small canine teeth, very much like our own today, left footprints like ours today. They were fruit and nut eaters. Dentally they were not pre-adapted to eat meat. Sussman challenges, “(Australopithecus afarensis) didn’t have the sharp shearing blades necessary to retain and cut such foods…These early humans simply couldn’t eat meat. If they couldn’t eat meat, why would they hunt?”

Predators living at that time were massive and numerous. Imagine hyenas as big as bears, saber-toothed tigers, and an overabundance of other mega-sized carnivores, reptiles and raptors. Australopithecus afarensis didn’t have tools, didn’t have big teeth and was three feet tall. She was focusing her brain, her agility and her social skills on getting away from giant, ferocious predators. “He wasn’t hunting them,” says Sussman. “He was avoiding them at all costs.” Their predation rate was similar to the rate of today’s savannah prey, 6 to 10 percent. A sensible theory is that our modern traits of cooperation and social organization developed not as a result of systemic hunting, but in honing our abilities to out-smart our predators.

From our origins we were an edge species living in the trees and on the ground. Food opportunities were ample from at least two plant-plentiful ecosystems. Needs for nourishment were satisfied. Our early ancestors’ habitat gives Sussman added indication, “Primates that are edge species, even today, are basically prey species, not predators.”

While quadrupedal primates typically have well-developed canines, our predecessors australopithecines did not have canine defense weapons against the vicious predators of those times. Upon the origins of our ancestors in this environment, why did canines shrink? Was Darwin accurate in postulating that the origins of free use of arms led to the advantage of using sticks and stones as weapons, shifting the locus of self-defense from teeth to arms?

Munford reasons,

The evidence suggests that the long struggle for bipedal survival and ultimately human dominance over all other species began when the australopithecines differentiated themselves as animals which walked, ran and fought on their back legs only, and could use their hands and arms to wield weapons and to throw missiles, thus uniquely becoming able to drive away predators and competitors whilst avoiding combat at close quarters.

Could it be that from our earliest origins the freedom of hands, brought about by our bipedal nature, is in itself what brought about the first catalyst toward our eventual dominion? Munford continues:

…our missiles – first stones, later spears, arrows and bullets – can kill or maim quite unexpectedly from a distance without harm to ourselves. They (other animals) have learned that even to be seen, at a distance, by a biped, can be dangerous or even fatal. It is best to keep out of our way, at least during daylight. That is why we can often walk through a wood which is full of wild animals of all kinds and yet hear and see almost nothing. Modern animals have learned the need to keep out of our way and have passed the knowledge on genetically or by example to their offspring. Those who failed to learn this essential lesson have left no descendants

Unlike other animals, people have learned to transcend the limitations of their own bodies. What we cannot achieve with our own bodily apparatus, we have learned to achieve with the aid of external tools, equipment and weapons… Without sharp teeth, horns or hooves, first the australopithecines and then people learned to defend ourselves with missiles and to keep our enemies at a distance. The stone missiles of those bipedal apes were the first step in the direction of the more sophisticated missiles of the twenty-first century. And the long story of pre-human and human development which started with those bipedal apes – a story in which we bipeds gradually became complete masters of our environment (if not of ourselves) – began with them.

Was dominion and invasiveness imprinted in our ability to use our free arms to cast weapons in the beginning for self-defense? Some soundly speculate that our removal out of nature through language was another substantial catalyst. But what is more clear is that even when early humans did begin scavenging meat off predators’ prey, it was not possible for early humans to consume a large amount of meat, much less hunt, until the substantial catalysts of controlled fire and cooking, relatively recent inventions.

Australopithecines were partial tree-dwellers, retiring to the safety of tree nests at night. But by two million years ago they evolved into Homo erectus with structure and proportions even more similar to our own except for a smaller brain size. They lived in open landscapes and roamed into other climates and continents. How did they find safety to sleep at night with so many nocturnal predators? In order to expand with nomadic ways would throwing stones and swinging clubs be a viable option in darkness, or was a nighttime basecamp with fire required? Whatever led to controlling fire, how did that impact Homo diet, our culture, and our relationships with each other and in the world? Ability to make fire may have started primarily to scare away night predators, but then allowed us to expand further out of our original habitat by providing warmth in a cold climate, i.e. to become an invasive species into other ecosystems.

Additionally, use of fire for cooking radically altered our eating patterns, triggered a transformation of our biology and culture, entrenching us in the ways of an invasive species. If the roles of casting weapons and language are not certain in shaping the dominating nature of the human species, the control of fire certainly set us apart from and above others in such a way that sparked human invasion of all Earth.

As recently at 60,000 years ago we were increasingly widespread, but still only one species among many. We were not among the most powerful or numerous in a world of big and powerful animals. Unlike many of them, we weren’t then, now or ever a keystone species. Quite opposite, the more we’ve adapted and evolved the more we’ve honed ways harmful to ecosystems. From times of australopethicenes the hominid environment included a cornucopia of animals, many serving vital functions of ecosystems, virtually all now extinct. Human deep past was one of perpetual fright in the shadow of megafauna, but still exploration of niches and adaptation of ways to survive. These survival strategies laid the foundation for our taking life under human control, shaping and rearranging indigenous biotic communities, colonization of all Earth.

From around 50,000 years ago human populations formed into tribes expanding into and competing for territories. Indigenous animals were dominated and hunted, sometimes to extinction. While there had previously been rare instances of bloodshed between humans, this time was the beginning of organized warfare. The practice and mindset of exploiting all life on Earth was now set, perhaps the greatest catalyst toward our species’ invasive nature even before population pressures triggered the advent of agriculture.

Now we are a species aware of the peril of our own future, at our own hands. Given that No invasive species has ever voluntarily retreated back into its habitat, could our intelligence and awareness of our invasiveness spark a motivation and ability to be the first?

Ria

Advertisements

2 thoughts on “Earliest Catalysts of Human Evolution into an Invasive Species

  1. Pingback: Earliest Catalysts of Human Evolution into an Invasive Species – Vegan Primitivist

  2. Yet, sometimes, living wisely and sustainably is practiced. These days I’m wondering if patriarchy and it’s subsequent hellspawn, civilization, isn’t an adaption to abundance in the environment. In other words, when the going is good, the males want to be the leader. After they’ve trashed everything they hand the reigns back over to the females to prevent extinction.

    Liked by 1 person

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s