Many people around the world have heard of cannibalism, the act of consuming another of the same species. It is frowned upon in mostly every part of the world, yet in the animal kingdom it is seen as a part of nature.
There are 4 different “types” of cannibalism. The most common in the animal world is Sexual Cannibalism, in the female of a species mates and then eats the male of the same species. The next is size structured, in which the strongest and the biggest will eat the weakest and smallest. After that would be cannibalistic infanticide, which is when the mother will eat the weakest of her young. Last is Intrauterine cannibalism which takes place in the womb. It’s when strong embryos will “eat” the weaker for nourishment.
This could have a number of different reasons. Sexual Cannibalism’s reason could be to make sure that each creature only has one mate. Because the female wants only he r children to be the strongest so by mating with the strongest male and then eating him, she insures that. cannibalistic infanticide could have a lot of reasons. One could be to make sure that there are no “flaws” in the species, but eating the weakest or “flawed” baby. It could also just be another way of getting food. If the mother eats her flawed weak child, then it will give her the nutrition she will need to feed the rest of her young.
The history of evolution shows us that when there is a
pressure change that threatened the survival of an organism, the organism
evolves to continue living. That
shows us that for future evolution, for example, homo sapiens might start to
have more and more hair due to the recent climate change and issues of global
warming, so they can continue to live and keep warm throughout the decades to
come. If the world where to become
flooded, leaving very little land but enough for people to migrate and find new
sources for food and shelter etc., then we would have to find another alternative
to the way we live now. If people had to swim from point A to B, I don’t think
that we would necessarily grow gills, but I do think that our lungs would grow
larger and bigger. If you were to look at a mammal that lives in the water,
such as a dolphin, whale, or sea lion, they do not have gills. They need to
resurface from time to time to get oxygen. So, if the world did start to flood you could only imagine that people
would start to hold their breath longer and probably have webbed fingers and
toes to help swim in the water.
I don’t think that evolution can be determined by looking at
history and seeing what has happened. I believe to see the future in evolution you have to look to
the present and see what is happening now in front of you. If there are no selection pressures
maybe evolution will just start to get rid of what we don’t need, like the
pinky toe or the male nipple. The
problem with the theory of evolution is that there is nowhere near enough data
to say this is how evolution works.
The reason being for that, even though evolution is amazing on its own,
it takes centuries for it to occur.
Asexual reproduction is a form of reproduction, which only
involves one parent. Plants for example use asexual reproduction or in their
case vegetative reproduction. Vegetative reproduction is when parts of the old
plant fall off and develop into new plants. The new plants will grow very close
to each other and to the parent. This will cause a struggle for soil, nutrients
and light, and will consequently cause the plants to be less healthy. During
asexual reproduction there is no chance of an evolution occurring, the
offspring would almost always be of the same species and would be identical to
the parents, so diseases are also passed down directly from the parents to the
Sexual reproduction is reproduction involving the union or
fusion of a male and a female gamete. During sexual reproduction is that there
is a large chance of an evolution-taking place. The new species will be able to
adapt to environmental conditions, and the new character that is formed with
the mixed gametes of the parents so there is a chance that the parent’s
diseases would not be received by the offspring.
Sexual reproduction is important when talking about evolution because it
also facilitates the increase in fitness under natural selection, leading to
the 'best' combinations of genes. Sex can impede the increase in the fitness of
the population the how it can remain the dominant form of reproduction across
all manner of species. Sex at its foundation of merging of genes from different
individuals creates genetically unique genes. If the goal is to maximize
fitness by finding a particularly good combination of genes,
asexual reproduction - which increases a population's numbers at a much faster
rate than sexual reproduction works pretty well.
Meat eating has been said to go as
far back as 2.5 million years for humans. Fossils of tools used to butcher meat
are found to have gone back that far. It is believed that we started eating
meat because of the competition for food between other species. Craig B.
Stanford points to an example of this in the Bwindi Impenetrable Forest
National Park. This forest is the only forest where mountain gorillas and
chimps live together. Chimps eat meat while Gorillas don’t meaning that they
can coexist together because they have two different diets.
How meat eating affected the evolution of humans
Long ago when humans started to eat meat it triggered tons of
evolutionary changes. For one thing, our jaws have gotten smaller so we can
chew meat better. And because of our diets being chocked full of meat we have
evolved to have an improved ability to process cholesterol and fat. Also, scientist say that eating meat
helped our brains to grow bigger and our figure slimmer. All these positives
from meat though did not happen until we started cooking meat. To get the
caloric energy you get from meat you have to cook it. So we really didn’t start
reaping the benefits of meat until we discovered fire.
Being a meat eater isn't all positive
But everything that has evolved
from meat eating was not good. Because our jaws are downsized are teeth cannot
fit inside. So it’s rare to find someone who has perfectly straight teeth that did
not have any dental work on them. Also us evolving to cooking and using forks
and knives has made out big teeth useless because our food is so soft.
(2005, February 18). "evolving to eat mush": how meat changed our
bodies. Retrieved from
(Producer). (2010, August 2). Food for thought: meat-based diet made us smarter
[Audio Podcast]. NPR Series: The Human Edge. Retrieved from
This picture from left is of castings of teeth from a chimpanzee, Australopithecus afarensis and
a modern human
It is no easy task to predict what the future of
the human race will be. According to US News, “Humans are evolving
faster than ever before, picking up new genetic traits and talents that
may help us survive a turbulent future.” The human race,
which is a quite intelligent, evolves everyday. Until recently
scientists believed that the human evolution had slowed down, due to
the lack of visual changes, failing to look deeper into the issue.
Human are now evolving within their genomes and DNA, it has been
scientifically inferred that with so many changes within the human body
as opposed to the physical features, will one day start to change
humans outer body.
A recent study in the news, (available on livescience.com) shows that speculation
that changes in human mating patterns may be contributing to the
increase in autism. Others track how humans have morphed in response to
changing circumstances, including enhanced abilities to metabolize
sugar and fight disease. One of the biggest changes within human DNA is
that some humans are becoming more resistant to the HIV virus and it will
become more common in the future, as well as changes in human body
makeup. One of the factors of that is that it a new form of DNA testing
helps parents choose the genetic makeup of their children, rejecting
embryos with inherited flaws or embracing those with desired
traits—such as being the right sex. The future of human evolution is
based on the future of new testing techniques.
Sorry this is late, I thought I uploaded, but didn't...
we think of the mentally handicapped or those with mental disorders, we
instantly feel pity. We usually do not stop to wonder why or how a person
came to be stricken with the disability or disorder that afflicts them. I
find myself curious about why these disorders still exist generation after
generation even after all the scientific effort at uncovering the causes and
possible cures. A great deal of time and attention has been spent on how
these disorders came to exist and what might make them worse and how to
make them better, but there is still so much we still need to learn.
Thankfully, scientists have given us a great deal of information that can
be very beneficial in understanding, treating and hopefully someday curing or
preventing mental and emotional issues.
studies have shown that a genetic predisposition may be hidden in people that
makes them prone to certain characteristics that when provoked, can create
emotional or mental conditions. This predisposition, in conjunction with
a triggering event or simply by the quality in that person’s environment and
upbringing can cause these characteristics to become problematic and spark a
mental or emotional abnormality. This peculiar phenomenon is called the
to this theory, when provoked, a characteristic may go into overdrive, causing
a person to have a legitimately diagnosable illness. Environmental stimuli that
may cause such a thing to happen are social issues or trauma that may have
occurred at a young age.
of the most common problems that can cause such a change in people would have
to do with their parents. If a young person does not receive the right kind of
attention as they are maturing, it can cause emotional and social problems for
them later in life. An overbearing or judgmental parental figure can
cause a person to have low self-esteem, which could then inflict disorders such
as narcissistic personality disorder, social anxiety disorder or even
depression. Parents who get divorced have also been shown to cause
obsessive-compulsive disorder in as children of divorced parents tend to feel
they have a loss of control in their lives and obsessive-compulsive disorder is
a disorder driven by a person’s overwhelming need and drive for control.
disorders reveal themselves when people who are predisposed for the
characteristics are triggered by an emotional or social stress. This ignites an
inner need to balance themselves out, mentally. Sadly, they often emotionally
overcompensate; leaving them worse off then they were in the beginning.
The Cleveland Clinic Foundation, Initials. (2005, May 20). Narcissistic personality disorder. Retrieved from http://my.clevelandclinic.org/disorders/personality_disorders/hic_narcissistic_personality_disorder.aspx
Elana Pearl Ben-Joseph, MD, Initials. (2008, November). What causes ocd?. Retrieved from http://kidshealth.org/teen/your_mind/mental_health/ocd.html#
Amal Chakraburtty, MD, Initials. (2010, March 01). Causes of depression. Retrieved from http://www.webmd.com/depression/guide/causes-depression
Rashmi Nemade, Ph.D., Natalie Staats Reiss, Ph.D., and Mark Dombeck, Ph.D., Initials. (2007, September 19). Current understandings of major depression - diathesis-stress model. Retrieved from http://www.mentalhelp.net/poc/view_doc.php?type=doc&id=12998&cn=5
Cadena, Christine. (2007, November 16). How anxiety develops in children: the "diathesis-stress" model. Retrieved from http://www.associatedcontent.com/article/446920/how_anxiety_develops_in_children_the.html
Research Question: Like other initially controversial scientific theories, will evolution one day be universally accepted by society?
Evolution has been a controversial theory since the first day word reached out about it. But, this is not unlike many other theories which we consider true and indisputable today. For example, Copernicus' Heliocentric theory and Newton's gravitational theory. Copernicus' Heliocentric theory basically asserted that the earth was not the center of the solar system, but the sun. At the time, everyone believed in geocentric theory which said that the earth was the center of the universe. This theory was so novel and unprecedented, people were quick to scorn Copernicus and dismiss the theory as nonsense. The dissension around it did not end for later Galileo defended it. He was a supporter of Copernicus and was put on trial by the Catholic Church for defending something that they felt contradicted religion.They wanted the theory banned. This is almost the exact same scenario with evolution today. The Copernican theory gained legitimacy over time and became universally accepted. Newton's theory of gravity had similarly controversial beginnings yet no one contests it's admissibility today.
If history has taught us anything, it's although initially controversial, theories with strong foundations such as Evolution do become universally accepted over time. There is evidence of evolution gaining more support today. Although just 39% of Americans believe in evolution, as indicated by a Gallup poll in 2009, that number has been on the rise, especially with the newer generations. 74% of people with a post graduate degree believe in evolution. There are some creationist museums today that include evolution in their displays. Perhaps one day even religious people can believe in the basic concepts of evolution while still holding faith in their religion at the same time. With the number of people who believe in evolution on the rise with newer generations, it is safe to assume that we will one day live in a society which almost unanimously accepts evolution as true.
The thumb is arguably the best
adaptation humans have. We don’t think about it, and we take if for granted,
but the thumb is used everyday, and makes things so much easier. However we
didn’t always have thumbs, nor are we the only ones who have them. The first
actual record of a thumb, was back when the Dinosaurs roamed the Earth, the
most known is probably the iguanodon. So thumbs have been around for a long
time, even sauropods that walked on all 4 legs seemed to have some resemblance
in their feet to a thumb bone, But what about with humans?
One of the earliest apes (even before the Humans) that had
a thumb was called the Proconsul; This ape lived around 17-23 Million years
ago, Although not human, they evolved from the samerelative (The
Kenyapithecus) they are
one of the first mammals on record to have a thumb. The first humans ever were
the Homo habilis, they too had a thumb.
all just means the thumb is a hard evolutionary trait to trace, they appeared
way before humans and apes, but did not appear to be used as an opposable thumb
until the first mammals.Now here
are some pictures of animals with thumbs:
"Survival of the fittest"
is a term coined by Charles Darwin. Throughout Darwin's life he studied the
evolution of animals but he is most known from his work with birds on Galapagos
Island. What separates the two is survival of the fittest is a "race"
between the same species of animals where only those who are capable of
surviving the conditions presented to them. The Ginkgo tree, a native of Asia,
was in a race with its own kind. When forced to survive in extreme conditions,
the tree with the defensive adaptations survived where as the only thing left
of the other variety of tree is a mere fossil. Evolution is the process to
adapt to the conditions provided. The difference between evolution and
"survival of the fittest" is that "survival of the fittest"
is when one species is competing with itself with different varieties.
Evolution is when one species is constantly changing to better survive in their
generations, humans have had the competitive edge over other species on this
earth because of one amazing feature we have that other creatures don’t. Our opposable thumbs. We have these amazing appendages and we
use them to do things most other creatures couldn’t even begin understand. For those of you who don’t know, “an opposable thumb is a physical adaptation. An adaptation is a feature
that helps a plant or animal survive in its habitat. Adaptations can either be
physical (a part of the body) or a behavior an organism has developed.” Thumbs
have helped us with things we normally could never do. They let us hold things, make tools to
work and work those tools. They even
let us give thumbs up. They do so
much for us that we sometimes even forget how important they are. Years of evolution have let us go this
far with thumbs and they will not stop now.