ël Gizmos Name: Victor Tomas Date: 9-12-22 Student Exploration: Human Evolution - Skull Analysis Directions: Follow the instructions to go through the simulation. Respond to the questions and prompts in the orange boxes. Vocabulary: bipedal, canine, cranial capacity, cranium, evolve, foramen magnum, hominid, hominin, index, maxilla, orbit, palate, skull Prior Knowledge Questions (Do these BEFORE using the Gizmo.) 1. Label one of the skulls below as human and the other as a chimpanzee skull. Human Chimpanzee 2. What features did you use to identify which skull was human and which was chimpanzee? The mandables of the human are smaller, and the chimpanzee's teeth are bigger Gizmo Warm-up In 1924, a fossilized skull that looked very similar to a chimp skull was discovered. But the skull most definitely did not belong to a chimp. The location of the foramen magnum-a hole in the skull where the spinal cord exits-indicated that the individual was bipedal, or walked on two legs. This fossil was some of the earliest evidence of human evolution. Using the Human Evolution - Skull Analysis Gizmo, you will discover some of the ways that skulls can be used to learn about human evolution. Start by comparing two modern hominids: a human and a chimpanzee. 1. Examine the Front view of the Homo sapiens (modern human) skull. Then, use the Select skull menu to examine the same view of the Pan troglodytes (chimp) skull. How do the skulls compare? The chimpanzee's mandibles are more significant than the human's mandibles 2. Now, examine the Bottom view of the two skulls. How do they compare? The chimpanzee's teeth are more significant than the human's teeth. Reproduction for educational use only. Public sharing or posting prohibited. @ 2020 ExploreLearning™ All rights reserved
Activity A: Foramen magnum Get the Gizmo ready: . Select the Homo sapiens (modern human) skull. Opisthocranion Foramen magnum Orale Opisthion Introduction: Skulls, even from the same species, can have a wide variety of shapes and sizes. To compare skulls, scientists use measurements of certain features to calculate indexes. An index is a ratio of one measurement to another. An important index for measuring hominid skulls is the opisthion index. This index indicates the position of the foramen magnum in the base of the cranium. The opisthion index can indicate whether a hominid species was bipedal or not. Question: How does the location of the foramen magnum indicate if a species was bipedal? 1. Measure: Select the Bottom view. To determine the opisthion index for humans and chimps, follow the steps below and complete the table. . Turn on Click to Measure Lengths. Measure the distance from the opisthocranion to the opisthion, as shown at top right. Record the opisthocranion-opisthion distance in the table below. . Measure from the opisthocranion to the orale, as shown at bottom right. Record the opisthocranion-orale distance in the table. · To calculate the opisthion index, divide your first measurement by your second measurement. Multiply this number by 100. Species Homo sapiens 8.19 Pan troglodytes 2.85