Moorpark CollegeMATH 274Rickie_Stanford_-_Lets_Build_a_Cladogram.

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Let's Build a Cladogram! Introduction: C/adistics is one ofthe newest trends in the modern classification of organisms. This method shows the relationship between different organisms based on the pr... esence or absence of certain characteristics called "derived characters". Derived cl,aracters are the unique characteristics of a particular group of organisms. These characteristics are "evolutionary innovations" that arose in one group of organisms, but are not found in the older members ofthe lineage. Based on these derived characters, cladistics is used to determine the sequence in which different groups of organisms evolved. The organisms and their derived characters are then illustrated on a diagram called a cladogram. A c/adogram shows the evolutionary relationships among groups of organisms. Organisms that are grouped more closely on a cladogram share a more recent common ancestor than those farther apart. Purpose: 1) To make careful observations to determine the derived characters of a group of organisms. 2) To arrange the derived characters into a cladogram showing the relationships between the organisms. Materials: Pictures oflamprey, trout, caecilian, turtle, cat, gorilla, and human Procedure: 1. Make careful observations of the animals in the pictures you have been given. As you study each picture, determine ifthe animal has any of the characteristics that you see in the data table below. 2. Ifthe characteristic is present in the animal, place a"+" in the correct column, indicating that the animal has that particular characteristic. 3. Ifthe characteristic is absent in the animal, place a" - "in the correct column, indicating that the animal [Show More]

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