EVOLUTIONARY IMPERFECTION

Dan HarrisJohn Lones

Robert Norris Brendan Little

Subrina Thapa

Introduction Consilence of Inductions

Analogous structures, DNA/RNA, Fossil record, Homologous structures, Sexual Selection, Embryology, Continental vs. Oceanic Islands, Microevolution of bacteria, Artificial selection (dogs), Hybridization

However, imperfection is unique…..

Vitamin C Production?

Subrina Thapa

GUESS WHAT THIS IS?

Vitamin- C

an essential nutrient It also is a cofactor in enzymatic reaction

and several other collagen synthesis. protects our body from oxidative stress by

working like antioxidants.

OXIDATIVE STRESS

long term effects : sickle cell , parkinson’s , heart failure, bipolar disorder, schizophrenia

Short term effects : prevents aging

Lack of Vitamin – C

DO WE MAKE VITAMIN- C ?

“Enzymological studies in the late 1950s revealed that the genetic defect was caused by the deficiency of L-gulono-y-lactone oxidase GLO, the enzyme that catalyzes the terminal step of L-ascorbic acid biosynthesisin most animals.” However, recent study show that the human genome contains a nucleotide sequencet hat cross-hybridizes toa cDNA for rat GLO. But a frame-shift mutation has made these genes non-functional

WHY DON'T HUMANS AND OTHER PRIMATES SYNTHESIZE VITAMIN C

70 - 80 million years ago Early primates lived in tropical regions

and ate lots of fruits (e.g. they were largely frugiverous), and therefore the mutation was not lethal to these animals and was passed on to all descendents.

So just like they say “ what you don’t use you loose” we too have lost the ability to synthesize Vitamin-C

PROBLEM Now we moved out of tropical environments, developed agriculture, started traveling on ships, planes and eating can goods. The repressed ability to synthesize Vitamin-C is in high demand. However, now the question is will it reselect this trait.

Evolutionary Imperfection of the Eye

Dan Harris

The Eye

“Irreducibly Complex???” Proponents of Intelligent Design

Far too complex to be “evolved”i.e. evolution is built of emergent properties,

however, if one took a component of the eye, there would be no eye

However, evolution works differently says Dr. Kenneth Miller from Brown University

Evolution of the Eye

Imperfection(s)•Acute Glaucoma •Aqueous blockage•Very painful•Temporary to permanent vision damage

Scotoma Commonly known as the blind spot Caused by an optic nerve infraction upon

the light entering the eye Test!

Take a blank sheet of paper Draw an “X” on the right side of the paper and

an “O” on the leftCover your right eye and focus on the “X”Very slowly move toward the paper and watch

the “O” disappear!

BIOLOGICAL IMPERFECTION OF CHOKING

Basics of Choking “When someone is choking with a

completely blocked airway, no oxygen can enter the lungs. The brain is extremely sensitive to this lack of oxygen and begins to die within four to six minutes.” - John P. Cunha, DO, FACOEP

Basics Continued There are two openings in the back of

the mouth:1. The esophagus where food travels to

the stomach2. The trachea where air passes to the

lungs

Basics Continued When something is swallowed the trachea

is covered by a flap called epiglottis. The trachea splits into left and right

bronchus which lead to the left and right lungs.

When an object ends up in the airway, it gets stuck when the airway narrows. Often times large objects get stuck just inside the trachea.

Speech The cause for the biological imperfection of

choking in humans is speech. According to scholar Neil Shubin: “We produce

speech sounds by controlling motions of the larynx, the back of the throat, and the tongue. All those structures are relatively simple modifications to the basic design of a mammal or a reptile...

Price of Speech “... In humans, the back of the throat...has flexible

walls that can be widened and narrowed by relaxing and contracting a number of muscles. The human tongue, too, is woven of multidirectional muscle fibers that give it a remarkable range of movement. By changing the size and shape of the mouth cavity and the softness or rigidity of the throat, we are able to modify sounds from the larynx.”

Functions at Odds Shubin continues to note that because we

use this flexible passage to swallow, breathe, and talk, “those functions can be at odds, for example when a piece of food ‘goes down the wrong pipe’ and gets lodged in the trachea.”

What’s different about humans? When comparing humans to other animals

Shubin observes: “Other mammals, and reptiles too, use the same

structures for eating, breathing, and communicating but the back of the mouth does not need to be so vertically spacious and flexible as ours. The basic mammalian structures are arranged so that nonhuman animals can safely swallow while breathing. Tweaking the engineering to enable us to talk has left us peculiarly vulnerable.”

Choking Conclusion With the useful biological development

for complex speech, we became more susceptible to the perils of choking.

Sources:-Shubin, Neil. "Fish out of water: human ailments as varied as hernias, hiccups, and choking are a legacy of our 'fishy' ancestry." Natural History Feb. 2008: 26+. Academic OneFile.- Cunha, John P. “Choking Overview” http://www.emedicinehealth.com/choking/article_em.htm

TESTICULAR HERNIATION

John Lones

Hypthotheses Introduction Hypotheses describing the evolutionary

origin and functioning of the scrotum The molecular physiology of testicular

descent in modern mammals Material and character coding

Tree topology/ results Evolutionary scenario of testicular

descent and scrotal development Adaptive significance of the scrotum and

testicular descent Conclusion

Evolutionary Significance Sperm need an environment at a

temperature lower than 98.6 degrees Fahrenheit

The scrotum allows optimum sperm production, however it is not void of imperfection

There is an opening to allow the Vas Deferens connectionThis opening however can cause a painful

hernia that must be corrected.

Bipedalism

Robert Norris

Evolutionary Imperfection of Bipedalism Bi-Pedlelization

Load on the lumbar compared to quadpidals Load on Knee

Load on Lumbar

Load on Lumbar increases as Gestation Period Increases

Male and Female Dorsal Wedging

Bird Vs. Human

Angle of the Knee

Quadruped Vs. Ancestors

The femur sits nearly perpendicular to the ground in a quadruped, while the femur sits at an angle in a biped. The A. afarensis Lucy exhibits a distinctly angled femur.