Bio lab

Lab Evolution: Evidence of Change
Interpreting Events from Fossil Evidence
Purpose: In this investigation, you will use some present-day knowledge and common sense to interpret fossil evidence.
Background Information:
    A fossil is defined as the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock. Types of fossils include mold fossils which are negative impressions of an organism. A cast fossil which is formed when the negative impression of a mold fossil is filled in. Trace fossils which are formed from footprints, nest, burrows, etc. And true form fossils which are fossils of the actual animal or animal part.
Hypothesis: N/A
Variables:
Controls-the different figures
Independent-none
Dependent-Interpretations of fossil evidence
Materials: Pencil and Paper
Procedure:
We observed Figure one.
We identified how many animals were in the figure.
We then did our best to determine what happened in Figure 1.
After we had a hypothesis to what happened in Figure 1 we answered questions 1-5.
We then repeated steps 1-3 on Figure 2.
After repeating those steps we answered questions 1-3
Data Collection:
Figure 2
Data Analysis:
Part A. Refer to Figure 1 and answer the following questions in complete sentences.
How can you tell in which direction the animals are walking?
    By the direction their toes are facing.
Did any of the animals change speed i.e. start running? When (give evidence from the figure)
    Yes, the animal at the top of the Figure began running about half way through his walk.     You can tell this because it lifts up its tail and begins taking longer strides.
How many different types of animals are represented? Explain your answer.
     Only two different types of animals are represented. The animal on the top’s footprint is slightly bigger than the animal on the bottom’s, but there footprints are still almost identical.
What might the lines between the footprints of the animal at the top and the animal at the bottom of figure 1 represent?
    The lines in between the feet of the animals most likely represent those animals’ tails.
If all the footprints were made within minutes of one another, which way was the wind blowing? Explain your answer. Hint: how can carnivores track their prey or how do prey know if a carnivore is nearby.
    If the footprints were made within minutes of each other, the wind was most likely blowing Northwest because the animal with the larger footprints was most likely hunting the animal on the bottom and did not want him to smell his scent. Also, the animal on the top most likely smelled the scent of the predator animal or the scent of the dead animal, which would have caused the animal on the top to run away believing there was danger.

Part B. Refer to Figure 2 and answer the following questions in complete sentences.
What season of year were these prints formed?
    These prints were most likely formed in spring because the tracks of these animals needed to be imprinted deep into the ground in order for them to fossilize, and in spring a lot of mud is produced, due to the large amount of rainfall, which would have caused the animals to produce deeper tracks.
How many different types of animals are represented? Explain
    There are three different types of animals here. This is because there are three very different sets of tracks visible.
Is it possible that the animals who made the footprints represented in the diagram never actually met each other at the same time? Explain your answer.
    It is possible because the bird creature could have come long before or after the other two and the other two animals could have just gone to the same spot to inspect something on the ground at different times.  But this is most likely not true as the two animals seem to be fighting.
Critical Thinking:
How would fossilized footprints be formed and preserved?
    When an animal makes an imprint in mud or sand, that ground then hardens where that imprint was, and is then covered over for millions of years by sediments in order to form a fossil.
What might depth of a footprint itself tell a scientist?
    The depth of the footprint could tell a scientist what the conditions were in the environment or how big the animal was. It could also tell how fast the animal was moving.
In what kind of environment did this all take place? Take into account the biotic and abiotic factors)
    These events most likely took place within a forest.
In what type of rock would you be most likely to find fossils? Explain your answer.
    Sedimentary rock is the best type of rock to form fossils because the process by which this type of rock is formed is the least likely to hurt whatever is being fossilized. Other rocks, such as igneous rock, are formed through extreme amounts of heat in the molten region of the Earth’s crust. Metamorphic rock can rarely have fossils within it, but due to the amount of pressure it undergoes during its formation, the fossils are most likely destroyed.
Would you be likely to find the fossil remains of a jellyfish or a cockroach? Explain your answer.
    You would be more likely to find the fossil remains of a cockroach because the cockroach’s exoskeleton is very rigid which allows it to be fossilized fairly easily, while the jellyfish has no skeleton and is quite soft which makes it impossible to fossilize.
The exposed rock layers of the Grand Canyon are rich with fossil specimens. What does the presence of fossilized coral, sponges, shellfish, and trilobites indicate about the past climate of the Grand Canyon area?
    These fossils indicate that the Grand Canyon most likely was covered in water and hosted a large amount of life within its waters.
Scientists have found fossils of the same kind of organism on different continents. How might this have occurred?
    This is most likely due to the fact that billions of years ago all of the continents were all connected to form a supercontinent called “Pangea.” And because all of the continents were bordering and touching one another, animals of the same species were able to live within two continents. However, over billions of years, the continents began to shift away from one another to form the way our current continents are placed.
Conclusion:
In figure 1, a bird like creature was walking along when it was eaten by a predator.  As the wind was blowing Northwest, the original bird creature could not sense the predator.  Also, the wind blowing Northwest allowed the other bird like creature to sense the predator and run away without being noticed by the predator.
In figure 2, the bird like creature on the right was either there before of after the two other animals.  The bird like creature most likely flew away, explaining why its tracks disappear.  The other two animals most likely saw food and started fighting for it, explaining the jumble of footprints from both animals.
    Some things that are bad about the experiment is that there are many interpretations that can be made about the two figures, so there is no right answer.  A solution for this is to add more clues to the Figures that allow the student to have a better understanding of what is happening in the two figures.