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Evidence of Evolution Lab Resources

Part I:  BIOLOGICAL EVIDENCE-
Homologous structures
Start bu coloring bones first, than complete table and question at top of back of page
 
COLOR CODE the BONES on back of page 1 using this key:
HUMERUS=red
RADIUS=yellow
ULNA=green
CARPAL=blue
Metacarpal, phalanges (all finger bones)=orange
  
Homologous structures are formed in similar ways during embryonic development and share like arrangements; however, they share somewhat different forms and function.


Part II:  More BIOLOGICAL EVIDENCE-
Analogous structures
You will need to research using google search what a butterfly wing and bird wind is made of (that is what they mean by structure)?
Also, research what taxonomy is and how butterflies and bird are classified?  Are they the same or different?

Analogous Structures differ in structure but are similar in function.
 



Part III:  More BIOLOGICAL EVIDENCE-Vestigial Structures
Vestigial Structures are organs or structures that have lost their function in an organism and become reduced in size.
Leg bone is a whale is a vestigial structure.


 
 

TAILBONES:
 Grandpa didn’t have a tail, but if you go back far enough in the family tree, your ancestors did. Other mammals find their tails useful for balance, but when humans learned to walk, the tail because useless and evolution converted it to just some fused vertebrae we call a coccyx.
The coccyx, or tailbone, is the remnant of a lost tail. All mammals have a tail at one point in their development; in humans, it is present for a period of 4 weeks, during stages 14 to 22 of human embryogenesis. This tail is most prominent in human embryos 31–35 days old. The tailbone, located at the end of the spine, has lost its original function in assisting balance and mobility, though it still serves some secondary functions, such as being an attachment point for muscles, which explains why it has not degraded further.  In rare cases congenital defect results in a short tail-like structure being present at birth. Twenty-three cases of human babies born with such a structure have been reported in the medical literature since 1884

WISDOM TEETH:
Wisdom teeth are vestigial third molars that human ancestors used to help in grinding down plant tissue. The common postulation is that the skulls of human ancestors had larger jaws with more teeth, which were possibly used to help chew down foliage to compensate for a lack of ability to efficiently digest the cellulose that makes up a plant cell wall. As human diets changed, smaller jaws were naturally selected, yet the third molars, or "wisdom teeth," still commonly develop in human mouths.[18] Currently, wisdom teeth have become useless and even harmful to the extent where surgical procedures are often performed to remove them.

 
BODY HAIR/ GOOSEBUMPS:
 Humans also bear some vestigial behaviors and reflexes. For example, the formation of goose bumps in humans under stress is a vestigial reflex; a possible function in human evolutionary ancestors was to raise the body's hair, making the ancestor appear larger and scaring off predators. Raising the hair is also used to trap an extra layer of air, keeping an animal warm. Due to the diminished amount of hair in humans, the reflex formation of goose bumps when cold is also vestigial.


EAR MUSCLES:
The ears of a Macaque monkey and most other monkeys have far more developed muscles than those of humans, and therefore have the capability to move their ears to better hear potential threats.  Humans and other primates such as the orangutan and chimpanzee however have ear muscles that are minimally developed and non-functional, yet still large enough to be identifiable.  A muscle attached to the ear that cannot move the ear, for whatever reason, can no longer be said to have any biological function. In humans there is variability in these muscles, such that some people are able to move their ears in various directions, and it has been said that it may be possible for others to gain such movement by repeated trials. In such primates the inability to move the ear is compensated mainly by the ability to turn the head on a horizontal plane, an ability which is not common to most monkeys—a function once provided by one structure is now replaced by another.

LITTLE TOE:  At some point in time the little toe was probably much longer and helped support, balance, and assist in climbing.  Over time the little toe reduced in size because we now stand upright and do not climb!




Part IV:  More BIOLOGICAL EVIDENCE-
Embryology Similarities in Development



Part V:  GENETIC EVIDENCE-Comparing Genes

DNA is the code for making proteins, the closer the DNA, the closer the proteins are. Look at the following data:

Amino Acid Sequences

Baboon

ASN

THR

THR

GLY

ASP

GLU

VAL

ASP

ASP

SER

PRO

GLY

GLY

ASN

ASN

Chimp

SER

THR

ALA

GLY

ASP

GLU

VAL

GLU

ASP

THR

PRO

GLY

GLY

ALA

ASN

Lemur

ALA

THR

SER

GLY

GLU

LYS

VAL

GLU

ASP

SER

PRO

GLY

SER

HIS

ASN

Gorilla

SER

THR

ALA

GLY

ASP

GLU

VAL

GLU

ASP

THR

PRO

GLY

GLY

ALA

ASN

Human

SER

THR

ALA

GLY

ASP

GLU

VAL

GLU

ASP

THR

PRO

GLY

GLY

ALA

ASN

1. For each primate, count the number of amino acids that are different from the human sequence. Record these numbers in the data table below.

2. Calculate the percentage differences by dividing the amino acid differences by 15 and multiplying by 100. Record these numbers in the data table.

Primate

# of Amino Acids Different from Humans

Percent Differences

Baboon

   

Chimpanzee

   

Gorilla

   

Lemur

   


Part VI:  FOSSIL EVIDENCE-Law of Superposition


CONCLUSION:

Evidence of Evolution Editorial Writing