NGSSS Science Supplemental Resources
student Packet
Biology
SC.912.L.15.1
Department of Mathematics and Science
THE SCHOOL BOARD OF MIAMI-DADE COUNTY, FLORIDA
Perla Tabares Hantman, Chair
Dr. Lawrence S. Feldman, Vice Chair
Dr. Dorothy Bendross-Mindingall
Susie V. Castillo
Dr. Wilbert “Tee” Holloway
Dr. Martin Karp
Lubby Navarro
Dr. Marta Pérez
Raquel A. Regalado
Julian Lafaurie
Student Advisor
Alberto M. Carvalho
Superintendent of Schools
Maria Izquierdo
Chief Academic Officer
Office of Academics and Transformation
Dr. Maria P. de Armas
Assistant Superintendent
Division of Academics
Mr. Cristian Carranza
Administrative Director
Division of Academics
Dr. Ava D. Rosales
Executive Director
Department of Mathematics and Science
Introduction
The purpose of this document is to provide students with enhancement tutorial sessions that will enrich the depth of content knowledge of the Biology 1 course. Each tutorial session is aligned to Biology Annually Assessed Benchmarks of the Next Generation Sunshine State Standards (NGSSS) as described in the course description and the Biology Item Specifications and include an ExploreLearning Gizmos activity and/or a science demonstration followed by assessment questions.
The Nature of Science Body of Knowledge (BOK) is embedded in all lessons. Teachers are encouraged to generate an inquiry-based environment where students grow in scientific thinking while creating and responding to higher-order questions.
Table of Contents
Classification, Heredity, and Evolution - SC.912.L.15.1 Explain how the scientific theory of evolution is supported by the fossil record, comparative anatomy, comparative embryology, biogeography, molecular biology, and observed evolutionary change. (Also assesses SC.912.N.1.3, SC.912.N.1.4, SC.912.N.1.6, SC.912.N.2.1, SC.912.N.3.1, SC.912.N.3.4, and SC.912.L.15.10)
Activity 1 - Human Evolution – Skull Analysis 3
Activity 2 – Evidence of Theory of Evolution 16
Activity 1 – Human Evolution – Skull Analysis
Learning Objectives
Students will …
· Measure and observe anatomical features on a variety of hominid skulls.
· Use the foramen magnum to identify whether a species was bipedal.
· Estimate the cranial capacity of various hominids.
· Compare the maxillary angle, dentition, and palate shape of various hominids.
· Use anatomical features to hypothesize evolutionary relationships between species.
Vocabulary
· Bipedal – walking on two legs.
o The first bipedal hominins evolved around 6 million years ago. It is from these hominins that humans eventually evolved.
· Canine – a pointed tooth that is used by most animals for grasping and piercing food.
o Canines are found only in meat-eating animals or animals that evolved from meat-eaters.
· Cranial capacity – the interior volume of the cranium, where the brain is housed.
o Humans have a cranial capacity of 1,000–2,000 cm3. Chimpanzees have a cranial capacity of 300–400 cm3.
· Cranium – the portion of the skull that does not include the mandible (lower jaw).
o The human cranium is generally composed of 29 different bones.
· Evolve – to change over many generations.
· Foramen magnum – a hole at the base of the skull through which the spinal cord exits.
· Hominid – a member of a group of primates that includes orangutans, gorillas, chimps, and humans.
o Modern hominids are also known as the great apes.
· Hominin – a member of the evolutionary lineage that led to humans.
o The ancestors of chimpanzees and hominins split into two separate groups around 6–7 million years ago.
· Index – a ratio of one measurement in relation to another.
o One common index is the body mass index, which is used to compare a person’s height to his or her weight to determine whether he or she is in a healthy weight range.
· Maxilla – the upper jaw.
· Orbit – a hollow in the skull for an eyeball.
· Palate – the roof of the mouth.
· Skull – the bones that make up the head of an animal, including the cranium and mandible (lower jaw).
Engage Activity: (whole class 15 minutes)
Your teacher will create discussion from the following stems using Socratic-like structure:
· Site some examples that serve as proof that evolution is real. List example why not.
· If our ancestors were apes, then why are there still apes?
· If we are evolving, what do you think we will look like in one million years?
· How do you think birds evolved flight?
Lesson Overview
What can an anthropologist tell from looking at an organism’s skull? As it turns out, a lot! From a skull alone, anthropologists can get an idea about how the organism moved, what it ate, how large its brain was, and much more.
Using the Human Evolution – Skull Analysis Gizmo™, students will explore some of the methods anthropologists use to analyze fossilized hominin skulls in order to learn more about human evolution.
The Student Exploration sheet contains three activities:
· Activity A – Students relate the position of the foramen magnum to bipedalism.
· Activity B – Students compare the cranial capacities of various hominid skulls.
· Activity C – Students compare the maxillary angles, dentition, and palate shape of various hominids and describe trends in hominid evolution.
Scientific Background
Human evolution is a fascinating and constantly changing field of study. The idea that humans evolved was first seriously considered by many scientists after Darwin published On the Origin of Species in 1859. Less than 10 years later, the first fossilized hominin remains (Homo heidelbergensis) were discovered in France. It took another 50 years (1924) for the first australopithecine fossil to be discovered in South Africa. In 1974, Donald Johanson excavated Lucy, the famous Australopithecus afarensis skeleton, in Ethiopia. This caused the interest in human evolution to explode. Today, fossil remains from at least 20 different hominin species have been found.
The most important hominid fossils are skulls. An enormous amount of information can be garnered by measuring and comparing the skulls of different hominid species. For example, in knuckle-walking apes the foramen magnum is located near the back of the skull. In humans and other bipedal hominins, the foramen magnum is located on the bottom of the skull. This arrangement allows bipedal individuals to comfortably look forward while standing up.
Scientists have found several 6–7 million year old transitional fossils showing the evolution of hominins. The oldest known unequivocally bipedal species is Australopithecus afarensis, which lived 3.9–3.0 million years ago. A. afarensis skeletons have ape-like skulls, but the lower body closely resembles humans. In addition, the foramen magnum of A. afarensis is positioned relatively close to the center of the cranium, indicating an upright posture. Several species dating 3.0–1.1 million years old likely descended from Australopithecus afarensis. These hominids are split into two groups: those with light builds, such as Australopithecus africanus, and those with heavy builds, such as Paranthropus boisei.
Around 2.4 million years ago, a new group of hominins appeared in central Africa. This group of hominins resemble humans closely enough that scientists have placed them in the Homo genus. One of the earliest of these hominins is Homo habilis, which still had many ape-like facial features, but had a very human-like brain shape—so much so that many anthropologists think H. habilis was capable of speech. Homo erectus most likely evolved from H. habilis. This was the first species to have definitely left Africa. H. erectus skeletons have been found across Europe, Asia, and even on the Indonesian island of Java. Homo floresiensis, excavated on another Indonesian island, is believed to be a pygmy form of H. erectus.
Many anthropologists think that Homo heidelbergensis, Homo sapiens neanderthalensis, and Homo sapiens evolved from H. erectus populations in Africa. These new species then migrated out of Africa and replaced the H. erectus species living in Europe and Asia. DNA evidence supports this theory, indicating that all modern humans are descended from a population that migrated out of Africa between 65,000 and 50,000 years ago.
Forensics Connection: Osteological evidence
Skull analysis is not only useful for studying evolution. The same techniques are also used by archaeologists and forensic investigators in order to glean clues from human remains. The skull, in particular, can offer a wealth of information to the trained eye. For example, the shape of the orbits and mandible can be used to determine an individual’s sex. The degree to which the cranium’s bones are fused can indicate a person’s age. The shape of the nasal opening and certain dental features can be used to determine ethnicity. The chemical makeup of teeth can pinpoint where a person lived as a child. Also, many diseases can be diagnosed by examining bone texture. All of this information can be compiled to identify remains, solve crimes, or piece together the life history of a historical figure.
Selected Web Resources
Interactive images of skulls: http://australianmuseum.net.au/Human-Evolution
Fossilized hominids: http://talkorigins.org/faqs/homs/species.html
Human evolution: http://www.becominghuman.org/, http://www.pbs.org/wgbh/aso/tryit/evolution/
Hominoid taxonomy: http://cogweb.ucla.edu/ep/Hominoids.html
Related Gizmo:
Evolution: Mutation and Selection: http://www.explorelearning.com/gizmo/id?554
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.
2. What features did you use to identify which skull was human and which was chimpanzee?
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.
· 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?
· Now, examine the Bottom view of the two skulls. How do they compare?
Activity A: Foramen Magnum
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.
Engage Question: How does the location of the foramen magnum indicate if a species was bipedal?
1. Get the Gizmo ready:
· Select the Homo sapiens (modern human) skull.
2. 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 / Opisthocranion-opisthion distance (cm) / Opisthocranion-orale distance (cm) / Opisthion indexHomo sapiens
Pan troglodytes
3. Analyze: The opisthion index is an indicator of where the foramen magnum is situated. The greater the opisthion index, the closer the foramen magnum is to the center of the cranium. This position is usually found in species that stand upright. A low value for the opisthion index occurs when the foramen magnum is situated in the rear of the cranium. This may indicate that the species walked on its knuckles or on four legs.
Using the index values you calculated, what can you conclude about humans and chimps?
4. Gather data: Humans, chimpanzees, and the other great apes are hominids. Hominids evolved from a common ancestor that lived about 13 million years ago. Hominins are hominids that belong to the lineage that led to humans.
Measure the opisthion index of the other hominids available in the Gizmo.
Species / Opisthocranion-opisthion distance (cm) / Opisthocranion-orale distance (cm) / Opisthion indexA. afarensis
A. africanus
P. boisei
H. habilis
H. erectus
H. heidelbergensis
H. sapiens neanderthalensis
H. floresiensis
5. Analyze: Hominins are characterized by bipedalism.
A. Based on their opisthion indexes, which of the hominids in the Gizmo are hominins?
B. Based on opisthion indexes, which hominin skulls are most similar to human skulls?
6. Explain: Why do you think the foramen magnum is positioned near the rear of the cranium for knuckle-walking species and near the center of the cranium for bipedal species?
Activity B: Cranial Capacity
Introduction: The brain is housed inside the cranium. The internal volume of the cranium is called the cranial capacity. The larger an organism’s cranial capacity is, the larger its brain tends to be.
Engage Question: How does the cranial capacity compare amongst hominids?
1. Get the Gizmo ready:
· Select Side view.
· Turn off Ruler, and turn on Click to measure area.
2. Measure: To estimate the cranial capacity of each skull in the Gizmo, measure the area of the part of the cranium that houses the brain. This part of the cranium is roughly behind the red line in the diagram at right. You can also use the three skull images below as a guide for measuring the rest of the skulls in the Gizmo.
After you measure the area of each cranium, multiply the result by 5. This will give you a very rough estimate of the species’ cranial capacity.
Species / Area of cranium (cm2) / Estimated cranial capacity (cm3)Pan troglodytes
A. afarensis
A. africanus
P. boisei
H. habilis
H. erectus
H. heidelbergensis
H. sapiens neanderthalensis
H. floresiensis
H. sapiens
3. Analyze: Examine the estimated cranial capacities you calculated.
A. Which species probably had the largest cranial capacities?
B. What do you think cranial capacity is a good indicator of?
C. Did any hominids have a larger cranial capacity than humans? If so, which species?