Human Under those circumstances, finches who were not

Human evolution is based off of multiple factors that influenced
each species. A crucial factor that affected humans was pathological diseases.

Diseases are problems in an organism that affect specific body parts, regions
and general bodily functions. In contemporary humans, there are various
life-threatening diseases that affect not only the individual organism, but the
offspring of the organism and surrounding organisms. Many diseases are
communicable, either from contact, water droplets, heredity, and genetic
mutation. Diseases have affected human evolution from the beginning of ancient
primates. Human evolution was affected through disease.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

            Evolution is a genetic
mutation of one generation that carries over into the next generation. Genetic
mutations can have positive and negative connotations. In reference to Charles
Darwin, his research and observations presented the deviations of species of
Finch on the various Galapagos Islands. The genetic mutations of the same bird,
can be seen in the physical characteristics of different species of the same
bird. This is a genetic mutation, in this example, Darwin’s finches, the finch
with the most suitable physical characteristic to survive to the environment
was able to thrive by attaining sufficient nutrients (2003:31-32) through the
way their beaks were shaped. This genetic mutation allowed for the finches to
adapt to their environment. The genetic mutation occurred in certain finch
organisms and not others. Under those circumstances, finches who were not as
well adapted (those without genetic mutations) could not attain appropriate
nutrients to survive in their environment, while those finches that had the
genetic mutation survived. Thus, mating occurred among predominantly between
genetically mutated, or evolved, finches and for multiple generations
thereafter, the species became a subset group from the original finches. Darwin
observed this pattern among the various finches along the coast, inland of the
island, and from island to island. Every finch in the environment had similar
traits, however there were no exactly similar traits from environment to
environment. This passing of genetic mutations, evolving of generations was
referred to by Darwin as “natural selection”. Natural selection is simply
stated as “survival of the fittest” (1980:41), or the organism with more
suitable genetic traits will be the organism that survives, so that organism’s
offspring will have the trait, so on and so forth. This is evolution because it
is the change of an entire species to adapt to an environment in order to

            Environment plays
a large role on the evolution of a species. From species to species, each
organism has their own genetic makeup that makes an organism stronger than
another, or smarter than the other. In reference to human genetic makeup, late
primate species are seen as hunchbacked, two legged organisms. Earlier humans
were more adapted to eating meat over plants. Their genetic makeup allowed for
the survivability to eat any animal or plant. On the contrary, early humans and
even contemporary humans are not able to consume all nutrients, vegetables,
fruits, plants, or animals. For example, dogs and canines are not all similar.

Most household dogs cannot eat chocolate because chocolate is poisonous for
dogs and can kill them if they eat enough of it. Similarly, all humans were not
similar in genetic makeup. Humans living in colder climates will have higher
tolerances to cold and provide themselves with material to survive in colder
temperatures, such as clothing and shelter. Humans in the desert will adapt to
the environment by living near water sources and obtaining food from a reliable
source, such as nomadic humans and gathering plants from cacti or desert oasis
plants. As was previously stated, environment plays a large role on the
evolution of a species. In the topic of human evolution and disease, humans
that were not genetically suitable through immunity to diseases or inability of
the human body to remove toxins and poisons would die and not pass their genes
to the next generation.

            The progression
of human evolution was affected by disease. Similar to environment, disease
would have been spread to human species through either animal or insect vectors
and specifically through heredity and genetics. Disease can be transmitted and
attained through physical transfer or heredity, that is from parent to child.

The inability to fight of microbes and viruses was the crucial aspect of human
evolution. For instance, the finches on the Galapagos Islands studied by
Charles Darwin needed to adapt their physical characteristics in order to
obtain nutrients from their surroundings. Similarly, early humans needed to
adapt their biological characteristics in order to survive against microbes and
viruses. The difference is the adaptations humans needed to go through were
microscopic changes. These changes derived from the host’s T-cells, leukocytes,
various biological advancements that would allow them to fight off diseases. A
disease such as influenza, for example, would not be easily extinguished today
if it weren’t for vaccines created by dead influenzae cells to boost
contemporary humans’ immune systems. The immune system of a human is split into
two subsets: active and passive immunity. Basically, passive immunity is
natural or what an organism is born with and given through the maternal milk,
in the case for humans; active immunity is the interaction between antibodies of
the host and the invading pathogens, influenza, E. coli, etc. Human A, a
female, and human B, a male, both are infected with influenza in the course of
their life. Their bodies natural antibodies fight off the pathogen and develop
an active immunity, that is their cells adapt and “learn” how to fight against
future invading pathogens. Human A and Human B mate and have an offspring that
will have the same antibodies from both parents, therefore the offspring will
have a passive immunity against the influenza strain because both parents
developed an immunity towards it. Evolution and the biological changes of a

            Disease and
environment are similar in the aspect that diseases are the normal flora of the
environment. Such as deer, rabbits, falcons, mountain lions are normal flora to
forests; diseases derive from the environment through toxins in plants, toxins
from animals, insects that spread animal-human disease, and especially the
genetic makeup of a human makes them more susceptible to a disease or diseases.

(1996:6-7).  Diseases can range from different sources, such as those
diseases from a non-human organism and viral diseases or diseases that are
within a human and mutated into a larger threat. According to Armelagos, he
stated that early hominids were nomadic, hunter-gatherer groups of people. A
nomadic tribe of hominids that hunted a herd that they were possibly following
and gathering food from trees, bushes, etc., was the dominant style of hominid
living. Diseases transmitted today from human to human are viral infections
that could have originated from any number of hosts. This being said, there is
a correlation between population and disease transmission because the more
people a human comes into contact with, then the higher the possibility of acquiring
a viral, bacterial, or communicable disease will be. Therefore a nomadic tribe
that could only sustain enough food for little amount of individuals would not
have the variety of diseases as contemporary humans do. Early hominids
continuously traveled along a herd in order to harvest their own meat and along
the way gathered any fruits from trees. Once these early hominids became
stationary, there must have been a style of agriculture and domestication of
animals. Armelagos claimed “reliance on agriculture increased the incidence
and impact of disease.” (1996:2-3)  As early hominids were able to provide
a stable set of food and domesticate animals such as horses, cows, oxen, etc.,
they became more susceptible for disease. If a population that grew an immunity
from generation to generation from nomadic style of life suddenly began growing
their own food and surrounded themselves with different animals, they exposed
themselves to diseases that the animals may have been carrying. The “presence
of domestic animals increased human contact with arthropod vectors,” (1996:3),
and from that increased mortality rates among the tribe. Disease and
environment are correlated from the ecological evolution of humans from a
nomadic lifestyle to a farming lifestyle.

            Evolution of
hominids towards contemporary Homo Sapiens was affected not only by the
arthropod vectors that derived from agriculture and farming, as well as the
normal flora of a human. Human flora is present with a variety of different
microscopic organisms, such as salmonella, herpes, papillomavirus, etc.

According to Van Blerkom, there are many groups of viruses that could have
possibly taken refuge in early hominids. She provided scientific evidence that
these viruses “co-evolved in close association with their hosts hominids.”
(2003:31) Referring back to Darwin and the theory of evolution, any organism
must be able to adapt to the environment over time. Environment, as described
early, is either from hunter-gatherer to agriculture and/or the flora of a
human. Viruses are not alive, in almost every discussion, viruses are not alive
because they cannot reproduce on their own, they need a host, and they do not
rest and digest. Viruses adapt and use their hosts to reproduce and infect
other organisms.Van Blerkom stated that viruses coevolved with hominids, this
means that early hominids adapted a biologic immunity to the viruses in their
normal flora, thus resulting in the viruses to adapt biologically through
genetic mutation and reproduction of host cells. This repetition of natural
selection shows that hominids evolved and adapted to diseases that were in
their environment over time. Armalego referred to the initial agricultural
lifestyle of nomadic hominids “increasing parasitic disease spread through
contact with human waste.” (1996:1-2) A tribe of people that suddenly changed
their way of life would not know to separate waste with water or food supply
because they never interacted with this problem before adapting to agriculture.

Through adaptation the tribes that learned this spread this knowledge of human
waste causing disease to further generations. Furthermore, the evolution of
human biology is present because for humans to be immune to diseases, their
body will need to provide the appropriate antibodies to fight off diseases such
as herpes, salmonella, influenza, malaria, etc. Many of these diseases harder
than others. However, according to Livingstone there are “two discoveries…of
the importance of natural selection in genetic variability.” (1980:28-29).

Livingstone refers to ABO blood groups and sickle cell anemia and thalassemia.

Assuming genetic variability is the variety of immunity among a population and
therefore the natural selection in genetic variability is the withering of
those organisms without proper immunity, then genetic variability is a factor
that determines the survivability of early hominids. Furthermore, Livingstone
continues describing the correlation of ABO with peptic ulcers, stomach
disease, and reproduction. Despite her claims that ABO blood groups had no
effect on the variability of a population, there is the clear distinction that
humans with certain blood groups were more susceptible to other diseases than
most and therefore had an effective immunity against pathogens due to
antibodies present.

            The effect of
diseases on human evolution can be described as the natural selection of human
genetic variability and early hominid populations to sustain and survive
against environmental and biological pathogens and diseases. Diseases provided
the biologically training of the early populations to develop stronger immunity
and adapt proper techniques to fight off diseases. Since many of these
diseases, such as Herpes, salmonella, E. coli, etc., “coevolved” (2003:31-32)
alongside the hominid genome, human evolution continued to undergo in order for
early hominids to survive, adapt, and eventually evolve into contemporary
setting humans. In contrast to neanderthals and other early hominids,
contemporary humans continue to develop strategies and immunity to fight off
diseases. For example, the change of hunter-gatherer to agriculturalists is
similar to the industrial and technological advances of the 21st century. The
natural selection of humans is still precedent today, however the advancement
of more resistant pathogens and the need for vaccines constantly prove that
evolution does not stop nor will it be unneeded for the survivability and
advancement of the human genome.