Cladogram Lab

By Ms Baker

First, a review of our “fossils”:

Specimen A

Specimen B

Specimen C

Specimen D

Specimen E

Specimen F

Specimen G

Specimen H

Specimen I

Specimen J

Chris shows us one way to examine a fossil.

Below are the results from one group (Sam, Mike S, Jack, and Alec).   Now, let’s debate!  What information do you disagree with?  How was your cladogram different/better?  What characteristics did you identify and how did you explain them?  In your comments, use research-based explanations with links to your evidence!

Ancestors of D, E, I, and J were seperated from the ancestors of A, B, C, F, G, and H because of an earthquake.  After several generations, the ancestors of D, E, I, and J developed holes because they needed a way to filter water to eat.  Habitat isolation led to these two groups developing new traits to the point where they were no longer able to mate with one another.

Competition for food between D, E, I, and J was really high.  Ancestors of species I developed joints so it could walk out of the water to find a new food source.  Because species I was symmetrical, it was caught by prey easily.  As a result, I became less and less symmetrical so it would not be caught by predators as easily.

Ancestors of species D were pulled by strong currents into an attractive fishing area.  They were seperated from their common ancestor between J and E.  Fisherman were able to harpoon ancestors of D.  Species D became transparent over time to avoid being caught.

The ancestors of E and the ancestors of J began to mate only with those like them, eventually causing them to be too different to mate.  This caused visible differences.

The ancestors of species A were the only ones that were moved by a growing mountain into a place where motion was still unecessary.  The other species grew joints to leave the water for protection against predators.

The ancestors of species b and g found the presence of symmetrly disgusting and only mated with those who are less symmetrical.  The ancestors of H, F, and C only liked those that had symmetry.  This eventually led to a split in species.

A group of the ancestors of species B traveled to a forest.  This species became transparent to hunt smaller organisms without being seen.

A rare event caused the bulk of the F, H, and C species to be split into three groups when an island was splint in a volcanic event.  By the time the volcano stopped erupting, species F, H, and C were no longer able to mate.

  • Vasiliki

    We use cladograms in order to organize things. They show how different groups relate to one another. They are classified into 7 groups. Kingdom, Phylum, Class, Order, Family, Genus, and Species.

  • Amy

    This is a great description of a cladogram and gives a clear description of the development of each specimen. In my group’s cardiogram, we agreed on the points that H, F, and C only mated with each other because they were symmetrical and they had the same type of symmetry and the point that B and G mated with each other because of the absence of symmetry. Regarding specimens D, E, I, and J, we thought that they shared a common ancestor that developed openings, but after this they branched off according to there symmetries or absence of. We thought that specimens B, I, and G branched off of from the other specimens because they did not contain any symmetry. We also said that specimens D, C, and G all had replaceable parts, but these parts developed in three different places, resulting in three different types of replaceable parts. Flexibility was another main point we addressed and in this we said that F, H, and C all had the same type of flexibility and could move in similar ways. Specimens B, I and G all had flexibility and had no symmetry, but they developed different ways of using there flexibility because of the different environments they were put in.

  • Erin

    This lab was so much fun to do but it was a lot harder than I thought it would be. I decided to learn more about the man who created the current system of classifying species, Carl Linnaeus. He was born may 23, 1707, in Stenbrohult. His father, Nils Ingemarsson Linnaeus, was a gardener and a Lutheran pastor. Carl disappointed his parents because from an early age he was interested in plants and animals, but had no interest in become a priest. In 1727 he went to the University of Lund to study medicine. After a year he transferred to Uppsala but their medical program had fallen into disrepair. Most of his time there was spent with plants as they were his primary interest. Several years later he completed his degree and published his first book on classifying species, Systema Naturae. He continued these studies many years and refurbished botanical gardens at Uppsala. Many of his students are famous today.

  • Marielle

    Carl Linnaeus developed the classification system. Before him pant names were long and complicated. Linnaeus gave each plants and animals a two part name :the genus and the species. He also divided them into two kingdoms and grouped them by characteristics. He is called the Father of Taxonomy. He was the first to group organisms correctley.

  • Alex

    I agree with Erin that the cladogram lab was much harder than expected! The cladogram has had such an impact on science over time, that I thought I would show a few examples on it’s affect. A cladogram is a is a visual reconstruction of the evolutionary history of a group of animals, based on the distribution of newly evolved features. Although cladistics provides us with the best current method of determining evolutionary relationships, it is not perfect. Contradictions among advanced features often suggest alternative evolutionary trees. But the cladogram is a great visual representation of evolution, and I really enjoyed this experiment!

  • Guy

    I agree with Erin and Alex the cladogram was very challenging. When Miss. Baker showed us a sample cladogram on the board I thought it was going to be very easy to create one. I had a lot of fun with this lab. It was very hard for such a simple lab. I think the component that made the lab challenging was that we didn’t examine real animals. We had to use our imagination and classify kitchen utensils as animals. I though Sam, Mike S, Jack and Alec’s cladogram was great. It classified the “animals” in a great way. I found out more information about cladograms at I found out that cladograms can be traced back to ancient Greece. I also learned that Darwin used cladograms during his expedition to classify all the newly discovered species.

  • Sam

    Being apart of this group was difficult, but by the end I definitely had a strong concept on how to make a cladogram. At first I watched my group member Jack sort out the information such as which specimens had holes and then I started drawing the cladogram using that information and seeing it all laid out rather then in data charts was much easier. Any category such as holes just means that any specimen on the line above holes, has holes. I did some more research on the cladogram and found a closely related word called Phylogeny. This word is clarified as comparing different body organs or structures to completely different organisms. This is done to find common ancestors between the two organisms. I also found the term homologous structure which is important in comparison of two different organisms because if the homologous structures are similar then there is a strong chance that the organisms are in some way closely related. To get more background on the cladogram visit these websites:

  • Adam

    Ms. Baker, this was one of the most interesting labs I have ever participated in this year thus far. It was really interesting to know how professional scientists organize different types of organisms. But although this was a really fun lab, it was really hard to figure out what these objects would possibly be if they were a fossil. And it was also hard to make categories for the organisms, as well as put the animal into that category. I decided to do some research on the history of the Cladogram. The creator of the classifying organisms was Karl von Linné, but in the science world, we know him as Carolus Linnaeus. In 1735, he released his most influential book called Systema Naturae. This book explains how to classify all of the known and yet to be discovered species on the similarities they posses. While this changed the way to classify organisms, another important biological figure known as Charles Darwin wrote the world famous novel The Origin of Species. This book backed up the theory of evolution using lots of evidence on his journeys. He also said that natural selection was the cause of all of these evolutionary changes. Because of this theory, Linnaeus decided to edit the way we classify organisms. It was at this moment that the Cladogram was born.

  • Lionel

    Ms. Baker, this lab really put us in the shoes of the scientist. We had a lot of fun in our different groups trying to figure out what these fossils could be. Phoenixia was a big help in our group. She was the leader, and taught Mike and I the fundamentals of the cladogram because we were absent last class. It became easy after i caught on. Without Charles Darwin’s book “The Origin of Species” we wouldnt we able to make some of the conclusions we did when we were completing this experiment.
    This site shows the step-by-step process to constructing a cladogram.

  • Cladogram Lab Activity | Using Blogs in Science Education

    [...] out this blog post a different group of my students wrote about this activity.  The post includes one of the [...]

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