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CLADOGRAMS. Branching diagrams that represent the phylogeny (evolutionary history) of a species or group. The characteristics shown on the line that points to the right are shared by the animals to the right. The characteristics farthest to the right are the most recently evolved.
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CLADOGRAMS Branching diagrams that represent the phylogeny (evolutionary history) of a species or group. The characteristics shown on the line that points to the right are shared by the animals to the right. The characteristics farthest to the right are the most recently evolved. animal(s) do nt have jaws? Which animal(s) have fur and mammary glands?
Create your own! Fossils show that one difference between ancestral forms of the modern horse, Equus, is the number of toes. Construct a cladogram using this information: • Eohippus (55 mya)—four toes • Mesohippus (35 mya)—three toes • Merychippus(26 mya)—one large toe, two small toes • Pliohippus (3 mya)—one large toe surrounded by a hoof • Equus (modern)—one large toe, more broad and flat, surrounded by a hoof *mya=million years ago
Eohippus Mesohippus Merychippus Pliohippus Equus two small toes three toes four toes broad and flat toe toe surrounded by a hoof one large toe
Cladogram Vocabulary A CLADOGRAM is a diagram that depicts evolutionary relationships among groups. It is based on PHYLOGENY, which is the study of evolutionary relationships. Sometimes a cladogram is called a phylogenetic tree (though technically, there are minor differences between the two). In the past, biologists would group organisms based solely on their physical appearance. Today, with the advances in genetics and biochemistry, biologists can look more closely at individuals to discover their pattern of evolution, and group them accordingly - this strategy is called EVOLUTIONARY CLASSIFICATION. CLADISTICSis form of analysis that looks at features of organisms that are considered "innovations", or newer features that serve some kind of purpose. (Think about what the word "innovation" means in regular language.) These characteristics appear in later organisms but not earlier ones and are called DERIVED CHARACTERS.
Create-A-Cladogram SB5. Students will evaluate the role of natural selection in the development of the theory of evolution.
Examine the sample cladogram, each letter on the diagram points to a derived character, or something different (or newer) than what was seen in previous groups. Match the letter to its character. 1. ______ Wings 5. ______ 6 Legs2. ______ Segmented Body 6. ______ Double set of wings3. ______ Jumping Legs 7. ______ Crushing mouthparts4. ______ Legs 8. ______ Curly Antennae
Create Your Own For the animals on the table, indicate whether the characteristic is present or not. Based on that chart, create a cladogram.