The Anatomical Structure Of The Human Body Is A Product of Evolution

Introduction

The anatomical structure of the human body is a product of 3.5 billion years of evolution. There are anatomical features passed down through this process from lower animals such as fishes, sharks, amphibians and other animals. Some of these features are not as obvious as the opposable thumbs passed down to us from the lower primates. The features I am talking about are responsible for inconveniences such as, appendicitis, hiccups and hernias we experienced occasionally because the design of the human anatomy was shaped from anatomical structures of lower animals.

To get a better understanding of this we must look back at the history of these animals I just mentioned. It was Charles Darwin who first realized that all higher animals develop from embryos that look almost exactly like in the early stages of development and then later begin to look different as they develop because they are different animals. This observation was one of the first steps that lead Charles Darwin to develop the Theory of Evolution; which has been proven in many branches of sciences such as genetics, pharmacology, biology, zoology and many more. Today it is no longer a theory based on hundred of proofs documented over the years. Back then Charles Darwin simply did not have the necessary scientific equipments and techniques such electron microscopes, PCR and electrophoresis to prove it. You will be surprised what these evolutionary hand-me-downs are.

Our Fishy Inheritance

Hernias is a problem some boys and men experience from time to time due to the results of evolution. This problem ocurrs because the gonads, the ovaries in the females and the testes in the males, were not originally in there present positions in the body. Both the ovaries and the testes were originally located right next to the liver during the early stage of embryonic development.  They were located there because the liver and the gonads were probably intereacting with the same tissues in that area during the early stages of development. Sharks and other cold-bloodied bony fishes gonads are still located next to the liver in their body to keep them warm.

Humans on the other hand are warm-bloodied. The gonads in the male fetus gradually descends from the liver down into the scrotum to place them in a cooler area away from the body to keep them at an optimum temperature to maintain sperm quality.  But what happened during descension, the spermatic cord that serves as the conduit for the sperms, had to take a round about way to reach the testes in the scrotum. A loop was essentially formed. The spermatic cord had to enter the scrotum through an opening at the bottom of the pelvis and since the scrotum is an outpocket of the body wall this created a weakness in the wall that can lead to hernias, a protusion of the intestine. The gonads also descended in the female but close enough to the uterus so that the eggs would not have far to travel. Females in general do not suffer from hernias.

The path of the phrenic nerve that control breathing
The path of the phrenic nerve that control breathing

Hiccups, Blame It on The Frog

Hiccups is another annoyances we have that can be explain through evolution. It can last a few minutes, sometimes days or even for years. Hiccups is caused by a spasm of muscles in the throat and chest. This is an involuntary response which means we cannot control it. Hiccups are triggered when we eat too fast or eat too much and in some cases are caused by a tumor in the chest.

Hiccups occur because we inherited anatomical features from two different animals on the tree of life. The fish is one and the amphibian is the other. We inherited the major nerves that control our breathing from fish and the hiccup itself was inherited from the past we shared with tadpoles. There is a group of nerves called the “phrenic nerves” that innervates the diaphram. The problem is that these nerves originate from the base of the skull and have to go through a series of twists and turns to make their way through the chest cavity and eventually end in the diaphram just below the lungs. There are a few structures along the way that can press on these nerves and irritate them thus interfering with our ability to breathe. A hiccup is the end result of this irritation. A better design would have been for the nerves to originate from an area on the spinal cord much closer to the diaphram.

Unfortunately, we inherited this design from fish with their gills closer to the neck and as we develop into a fetus the location of the origin of the nerves does not change, therefore the nerves that used to travel a short distant to innervate the gills to control breathing in fish must now travel further since the diaphram is far removed from the neck.

The other reason we may have hiccups because we inherited it from the tadpole. Some animals start their lives in water such as amphibians, specifically tadpoles, breathe with gills and lungs. They are able to do this because they have the right muscular structures and placement of nerves to produce hiccups naturally. The tadpoles must take in water and push it out through their gills for oxygen but at the same time they must keep the water from entering their lungs. So how do they do this? They close the glottis, a flap of tissue over the opening to the lungs, to close off the breathing tube to the lung while they are drawing the water in to push it out through the gills. Basically, what they are doing is a prolonged hiccup. Ours is much shorter. By the way that same flap of tissue that close our bronchial tubes is called the epiglottis.

Oh Our Aching Knees, They Weren't Design For Walking

Many of us often have problems with our knees because after 3.5 billion years of evolution they still are not design correctly for upright walking. Remember animals use to be only in an aquatic environment such as oceans and streams for a while. The major bones in our legs, wrists and backbone were not designed to support a lot weight, especially with the high incident of obesity. They were really design for swimming. Orthopedic surgery for knee replacements is at all time high for people below the age of 50. This is why we experience a lot of torn cartilages and ligaments in our knees and ankles. Almost all form of animals that walk on land eventually experience some form of bone disorder because of this design of the joints. Aquatic animals did not used these bones to support a lot weight. They were used for locomotion in the their watery environment, not to walk around on two feet.

Comparison of forearms and upper arms of various animals
Comparison of forearms and upper arms of various animals
Sickle Cell Anemia is the result of evolution. It is a hereditary disease
Sickle Cell Anemia is the result of evolution. It is a hereditary disease

Sickle Cell Anemia, One Example of A Disease Cause By Evolution

There are many modern day ailments we experience because of evolution. Many of these aliments ocurr in a few generations of the evolution process. For example, the very well known aliment called sickle cell anemia, a blood condition where the shape of the red blood cells are changed from their normal double concave disc shape to a sickle shape. The gene that control the shape of the red blood cells was altered in response to a parasitic infection from malaria carrying mosquitoes. The shape of the red cells were change to confer an immunity to malaria in people who live mostly around the mediterrean region of the world. The parasites in the mosquitoes’ saliva does not thrive in people with sickle cell anemia. Unfortunately, the trade off in immunity leaves people with this condition with serious debilitating pains throughout their body. Fortunately, it takes two carriers of the defective gene to produce an offspring with this condition.

Conclusion

As you can see the process of evolution is not necessarily a process of improvement all the times as most people think it is. Sometimes traits that were good for other animals in the tree of life may not be a good attribute for animals higher up in tree such as us. Eventually in time, these annoyances such as hiccups, hernias, joint pains and many more I did not discussed here such as goose bumps, extra ear muscle, extra eyelid, the appendix, etc., may eventually disappear through the process of evolution and become a thing of the past.

References:

  • Scientific American, January 2009, Volume 300, Number1, "This Old Body" by Neil H. Shubin
  • Wikipedia



© 2011 Melvin Porter

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Comments 32 comments

melpor profile image

melpor 2 years ago from New Jersey, USA Author

Natasha, thanks for your comment. There are few more of these evolutionary hand-me-downs I didn't mentioned. For example, the anatomical layout of the structure of our eyes were developed in lower animals before primates existed.


Natasha Peters 2 years ago

Great read! Another fascinating example of an evolutionary leftover is our "tail bones", which are obviously quite useless to us now. And another, the odd person's webbed toes and/or fingers!


melpor profile image

melpor 4 years ago from New Jersey, USA Author

Slockerham, I viewed the nearly 2 hour long video of Lloyd Pye's presentation based on his "Intervention Theory". It was interesting but the evidence he presented did not convinced me that we are a product of alien intervention. Where are these so called aliens and the planet Niribu? He said the planet comes around roughly every 36,000 years. That means this planet have passed earth seven times already if this hybrid species (modern man) has been on earth for 250,000 years. I think they would stop by occasionally to check on their creation from time to time. His presentation does not make any sense. Also I would think all the bigfoot creatures, if there were any, would have died out and became extinct by now since there probably were not that many of them around. Otherwise, we would have seen a lot more of them. Furthermore, Pye left out some very critical fossil evidence that show the smooth transition from early ape-like creatures to man. We did not come from apes, we come from the same roots that apes originated from that is why the apes and man are present today simultaneously.


slcockerham profile image

slcockerham 4 years ago from Tallahassee, Florida

What about this teaching video by Lloyd Pye at http://youtu.be/pe6DN1OoxjE


melpor profile image

melpor 4 years ago from New Jersey, USA Author

RJ, thank for your comment and reading my hub.


R. J. Lefebvre 4 years ago

melpor,

This hub was beyond my (mental capacity) closet with two ears. You must have a closet beyond the horizon, thanks for stretching mine!

Ronnie


moneycop profile image

moneycop 5 years ago from JABALPUR

haha strange!!! melpor please read my post first i have some clarifications in my article,

but here i am asking that we human are from thousands of years as it is and since when science had known the creatures none of them had changed, i agreed it can pass to generation, but of same species and DNA has a very little space to alter, so it can multiply but how come it will form new species, its like a joke...not on u ..don't feel..its when i understood the thing , its for those Darwin and many still believe the same...really strange!!!!

till now we should have 3-4 hands extra as development hahahaha!!!!


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Moneycop, I not quite sure what you mean by complete but we are still involving due to mutations passed on from one generation to the next. All animals and plants are constantly evolving from one generation to the next. This is how evolution works. Who knows in another hundred thousand years or so all animals and plants are going to look a lot different from what they are now and in some cases we will not be seeing some of these animals around due to extinction.


moneycop profile image

moneycop 5 years ago from JABALPUR

GOOD TO READ YOUR POST, BUT I HAD A DOUBT HOW DEVELOPEMT HAS STOPPED? ARE WE COMPLETE NOW?


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Thanks Trish_M. You are welcome to do so.


Trish_M profile image

Trish_M 5 years ago from The English Midlands

Hi :)

Very interesting indeed!

I find evolution a fascinating subject and I really enjoyed this item :)

I'll link it to some of my own hubs ~ I hope that's ok ?)


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Glassy, I am also fascinated with science of evolution because it pretty much explains everything from genetics, diseases, heredity and ways to treat these diseases by understanding it.


Glassy profile image

Glassy 5 years ago from Aus

Great Hub Melpor. Evolution always fascinates me.


nicomp profile image

nicomp 5 years ago from Ohio, USA

@gingersmaltese : The entire mythology of embryos passing through stages somehow 'proving' macro evolution is the crux of the problem.


gingersmaltese profile image

gingersmaltese 5 years ago from 27597

Thank you for that acknowledgment. The ten million dollar question now is, why is the "gill slit" myth still being published by scientific magazines and in biology textbooks? Its been over a hundred years since science discovered this fact. That gill slit error is far from the only error you will find used for support of evolution. You can see why so many people don't believe in macro-evolution with such deception going on in its support. The intellectually honest evolutionists should be outraged at all this false support being foisted around. It makes the theory look fake. I just so happen to think its not only fake in appearance but in fact.


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Ginger, you are correct and I am wrong. I apology to you and to all the other readers. Those folds are called pharyngeal pouches under the head of all embryos of higher animals. They are not gills slits as early scientists called them during the time of Charles Darwin. However, this is still the common feature that all higher animals share that indicates they all are explicably linked to one another through a common ancestor. Also bear in mind, the images Darwin saw at the time were not very clear images of embryos. Thanks for bringing this to my attention. I will make the correction in my hub.


gingersmaltese profile image

gingersmaltese 5 years ago from 27597

Your instance that the ear comes from gill slits in embryo is mystifying to me because Humans DO NOT have gill slits in embryo, period. Building a case on this fact is ridiculous because those diagrams you refer to (that Darwin referred to)are a proven undeniable fraud from over a hundred years ago. Your reference is wrong and its not surprising to me that you found some misinformation about evolution, there are several common frauds, deceptions and misrepresentations in modern textbooks on this issue. Do some research, you will see.

Maltese are a terrible example of evolution for a number of reasons. Firstly, Maltese look the way they do today because of the intervention of INTELLIGENCE in the breeding patterns of dogs. Secondly the process your referring to is natural selection, something nobody has a problem with, including ID people and creationists. There is a certain amount of variability built into the genome of all creatures in order to allow them to adapt and survive. This variability has limits biased on what genes are already present in the animal.

Thirdly, Micro-evolution is simply a result of natural selection or INTELLIGENCE acting on the available gene pool. The Macro-evolution you are talking about has never been seen to happen and there are no intermediate fossils to show that it ever did happen. Why have evolutionists been looking for these missing links for over a hundred years and yet to have found one out of millions of fossils?


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Nicomp, sickle cell anemia is a mutation of the shape of the red blood cells to protect us from malaria. Unfortunately, the sickle shaped blood cells cause pains in the joints of people that inherited the defected gene from both parents. Mosquitoes cannot infect people with sickle-cell anemia because they cannot use these cells in the malaria life cycle.


nicomp profile image

nicomp 5 years ago from Ohio, USA

Are you suggesting that sickle cell anemia is a positive mutation?


nicomp profile image

nicomp 5 years ago from Ohio, USA

"It was Charles Darwin who first realized that all higher animals develop from embryos that look almost exactly like in the early stages of development and then later begin to look different as they develop because they are different animals."

Actually, no. This is a hypothesis and cannot be proven. It was not a realization, rather a suggestion by Darwin to explain his findings.


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Gingersmaltese, our inner ear is an anatomical feature developed from these gill slits we have have as embryos. There are many evidence of traits we inherited from lower animals through the process of evolution. The strongest place to look is in our DNA. There are lots of strong scientific proofs that these traits are a result of evolution. Check the reference I listed to the Scientific American article where some of this information came from. The picture showing the comparative anatomy of embryos from various animals is what lead Charles Darwin to develop the theory of evolution. The theory of evolution is no longer a theory today. Scientists used this knowledge everyday to save lives and develop new treatment for illnesses and diseases through the science of genetics.

Genger, your maltese is a case that supports evolution. This breed of dog was developed by selective breeding over time to produce the dog you now have as your pet.


gingersmaltese profile image

gingersmaltese 5 years ago from 27597

You are aware that humans do not have gill slits in embryo don't you? That diagram you have is biased on a fraudulent woodcut used by a man named Earnst Haekel. He was fired from his teaching position after he admitted he fabricated the drawings of human gill slits. Try to find any "real" evidence for human gill slits, it doesn't exist. For over a hundred years this has been known, why are evolutionists still uninformed?

The thing that interests me most about his hub is that all your explanations for the various human conditions are stated absolutely, no maybe or might or could have. How are you so confidant about these things when there is no real data on what your speaking of, just speculation.

As for the part about knees not working correctly, There are numerous people who run hundreds of thousands of miles well into advanced age and have no knee problems. The reason people have bad knees is that they don't use them, siting behind a desk all day and then driving home to go to sleep does your knees no favor. Use it or lose it as they say.


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Superwags, I agree. There are plenty of evidence that show the progression evolution had occurred and it is still happening. We see it everyday and lots of people don't realize it. Every time we get sick and recover from it is a good example of evolution taking place.


superwags profile image

superwags 5 years ago from UK

Great hub Melpor, really enjoyed it. Something which fascinates me at the moment is the unlocking of the genetic codes of not just humans, but other species too. It's amazing to see genes occupying the same places in the codes of very low animals, as ourselves.

I guess the pax 6 gene is the most commonly used example of this, the one which deals with our vision. We share the gene with every other species with eyes or eye spots - right back to jellyfish - there's no example of eyes happing because of convergence at all!

This blows my mind and I'm sure would blow Darwin's too! It's incredible that people still quibble with Darwin on evolution; even the genetics back him up perfectly!


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Scott, thanks for your comment. The problem is people do not understand their science. Apes and humans evolved from a common lower mammal about four billion years ago. The apes did not change from their appearance as they appear more than four million years ago because they remained in the forest. They did not roamed the savannah like early man did. So they did not change much during that time period. There was no evolutionary pressure there for them to change. Man on the hand left the the forest and went out into the savannah and which came a lot of environmental stresses such finding food and water, the hot sun, roaming longer distance, etc., we change to bipedal animals and our brain size increased. Just to name few of the changes. Every living thing on earth are the descendants of single cell organism.


Scott 5 years ago

This has to be one of the biggest debated subjects of all time. But every time I hear an evolutionist spin their twist on how we evolved from the ape, there is never any mention as to how the ape evolved. Where and how did the ape come from? A fish? Where did the fish come from? A seed? Where did the seed come from? A random concoction of all the stars lining up in perfect unison? I don't think so. The theory of evolution is such a leap of faith being that the scientific odds of something coming from nothing just doesn't make sense.


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Rhonda, thanks for your comment and thanks for the compliment. Essentially we have something from every animal below us including the one-cell amoeba in our anatomical structure.


Rhonda Waits profile image

Rhonda Waits 5 years ago from The Emerald Coast

A very interesting and educational hub. Voted up and awesome. What will we learn next? Great hub.

Sweet wishes Rhonda


melpor profile image

melpor 5 years ago from New Jersey, USA Author

Qwark, thanks for the thumbs up and for stopping by.


melpor profile image

melpor 5 years ago from New Jersey, USA Author

TahoeDoc, thanks for your comment.


qwark profile image

qwark 5 years ago

Voted ya up on this one Melpor.

Very well written and backed up!

It'll turn off the "creationists" and unlearned religious skeptics, but if man lasts long enuf, the processes of "natural selection" will greatly diminish their numbers...lol :)

Qwark


TahoeDoc profile image

TahoeDoc 5 years ago from Lake Tahoe, California

Fantastic! Interesting, educational and fun. Thank you-)

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