Grade: 2
Using Scientific Knowledge in Life Science
- Evolution
All students will explain how scientists construct and scientifically test
theories concerning the origin of life and evolution of species
Explain how fossils provide evidence about the nature of ancient life.
Constructing and Reflecting
SCI.I.1.1 - Generate reasonable questions about the world based on observation.
SCI.I.1.2 - Develop solutions to problems through reasoning, observation, and investigation.
SCI.I.1.5 - Develop strategies and skills for information gathering and problem solving.
SCI.II.1.1 - Develop an awareness of the need for evidence in making decisions scientifically.
SCI.II.1.4 - Develop an awareness of and sensitivity to the natural world.
SCI.II.1.5 - Develop an awareness of contributions made to science by people of diverse backgrounds and cultures.
Vocabulary / Key Concepts
Fossils, extinct, ancient, paleontologist
Common contexts:
• plant and animal fossils
• museum dioramas
• paintings/drawings of ancient life and/or
Knowledge and Skills
Benchmark Clarification:
Scientists who find and use fossils to create an
understanding of the past are paleontologists. A
fossil is one of many tools used by scientists to
study the history of life on Earth. Fossils can take
many forms:
• An impression of a dead plant or animal that
has been replaced by minerals
• A cast formed by filling in spaces left from
footprints or decaying bodies
• A mold, plant, or animal trapped in tree sap
• A preserved specimen of life from a specific
Students will:
Identify the following types of fossils:
1. An impression of a dead plant or animal
that has been replaced by minerals
2. A mold of a footprint or a decaying body
that has been filled in with sand / clay
3. A fragment / whole animal that has been
trapped in tree sap
Coloma Resources:
Newbridge Early Science Program:
“The Big Bears” Teaching Manual and Big Book
“Animals in Hiding” Teacher’s Manual and Big
“The World of Dinosaurs” Pgs 6 & & (Teacher’s
Manual) Diorama pg 13)
Robins - book
Diggins - book
Play Dough - experiment
Cups – goes with above experiment
Creepy Crawlies - book
Fossil Collection - book
Fossil Kit - activity
Mix Up Chameleon - book
Match fossils with the time period when they
were most likely formed
Explain another tool scientists use to study the
history of life on Earth
Other Resources:
Museum of Paleontology – UC Berkeley
Dinosaur Thematic Unit – EXCELLENT – lots of
info, activities, resources – very teachable!
USGS – Fossils and Biographies of scientists
Dinosaur integrated unit from Southwest
Educational Development Laboratory –
“Changes over Time.” A Second Grade Unit by the
Battle Creek Area Mathematics & Science
“Fossils, Fossils.” Sing the Science Standards
ReachOut Michigan – make your own fossil print
with salt dough.
Anning, Mary.
UC Berkeley – Biography – Mary Anning
Other Resources (continued from column at right.)
Focus Question: How are Earth’s layers used to
determine the age of a fossil?
The teacher will collect and redistribute cups,
making sure that students do not receive their
own cups. Students will open their cups by
Begin by reading a biography about Mary Anning.
carefully tearing them down the sides.
Students should carefully explore the shapes
Students will create a model of fossil layers similar to and patterns that were made by their casts.
the Earth’s. Each pair of students will use
With a cautious approach, students may be
approximately one-third of a can of play dough (all
able to keep the molds of their specimens
one color or three separate colors) and two small
intact. The teacher will ask students which
items (twigs, leaves, bark, seeds, dead insects, fruit specimens made a good impression or
rinds, chicken bones, small shells, or small plastic
disintegrated, and which lived at an earlier
insects) to make fossil layers in a paper cup.
time or lived later. Students will draw
conclusions and present their findings based
Guide students through the following steps: Put one- on their observations.
third of the play dough in the bottom of the cup, put a
(Give students rubric before activity.)
specimen on top of the play dough, cover it with
Scoring Rubric
another one-third of the play dough and press, put
the second specimen on top of this layer, and cover
Criteria: Identification of layers
with the remaining one-third of the play dough and
Apprentice -Recognizes that objects were buried at
different levels (layers).
Students then will discuss which layers in the cup
Basic-Locates at least two distinct layers.
are the oldest and youngest. Students will explain
Meets -Locates all layers and finds evidence of fossils.
how this activity is similar to the idea that the age of
Exceeds -Locates all layers and explains that fragile
a fossil layer is determined by the order in which it
materials disintegrate and therefore not all plants and
animals from the past made fossils.
was formed.
Criteria: Demonstration of scientific methods
Apprentice -Preserves some evidence of the layers.
Basic-Preserves layers and some of the casts.
Meets -Preserves the layers and the casts.
Exceeds -Works meticulously like a paleontologist
and identifies the specimens precisely.
Criteria: Accuracy of relationships
Apprentice -Explains that some plants/animals lived
a long time ago.
Basic-Recognizes that fossils exist within layers of the
Meets -Describes the relationship between layers and
the age of specimens.
Exceeds -Provides evidence that not all members of
a species (i.e., dinosaurs) became extinct at once -orLinks climate and other natural disasters with fossil
Teacher Notes:
Explain how scientists construct and scientifically test theories concerning the origin of life and
evolution of species.
Are there patterns of similarity among organisms alive today? Are there relationships among organisms
that lived in the past and organisms alive today? Where did humans come from in the history of the world?
What is the evidence that might give us some clues to these questions? Many students come to the science
classroom with strongly held beliefs that don't allow them to openly examine the scientific explanations to
these questions. The challenge in the science classroom is to help students distinguish between a scientist's
way of thinking and understanding from those practiced by some theologians, poets, or philosophers.
Students need working definitions of key terms with clear examples to provide a framework for their
thinking. This should help them demarcate where science begins and ends. Words such as fact, theory,
hypothesis, and law are terms students encounter in casual conversation in everyday life. In science these
terms have a very specific meaning. A fact is an observation that has been repeatedly confirmed but facts can
change. It was a scientific fact for many years that human cells had 24 pairs of chromosomes. Improved
techniques of microscopy revealed that they actually have 23 pairs.
People commonly use the word theory to mean a "guess" or "hunch". "My theory is..." in common usage
would be better stated as "My hypothesis is....". In science, a hypothesis is a testable statement about the
natural world. A theory, in science, is a well-substantiated explanation of some aspect of the natural world. It is
a powerful idea that represents our best explanation at this time. The abundance of supporting evidence
makes the subsequent abandonment of a theory unlikely. Theories can be continually refined and even
replaced with an alternative theory in light of new and compelling evidence.
Finally, laws are generalizations that describe phenomena whereas theories explain phenomena. The laws of
thermodynamics describe what will happen under certain circumstances; thermodynamic theories explain why
these events occur. A clear understanding of these terms should provide students the structure needed to
begin the study of evolution.
It is important for students to be able to distinguish between evolution and the proposed mechanism, which
accounts for its occurrence. Evolution is the historical change in life forms that is well substantiated and is
generally accepted as fact by scientists. Students should explore the similarities of vertebrate's limb structures
such as the forelimb of a chicken or bat, human, whale, cat, and lizard. They may also study similarities in the
early development of vertebrate embryos. Students need an opportunity to observe, from the fossil record,
kinds of organisms that once lived on earth but now are extinct such as the Petoskey stone's, Hexagonaria
percarinata, trilobites, or crinoids. They can examine the apparent relatedness of fossils to one another and to
organisms living today. This will begin to lay the groundwork for evidence of common ancestry.
Students are naturally drawn to questions of their own ancestry. Students can perform a simple
comparison for similarities and differences when given pictures or models of a gorilla, a modern human, and a
hominid fossil skull. Patterns will emerge as students discover intermediate traits and forms. Further study of
the relationships of humans to other selected animal groups can be done by looking at DNA and blood protein
similarities. Vestigial structures such as the appendix, tailbone, wisdom teeth, and ear muscles also give
evidence to common ancestry with selected animal groups.
Patterns and evidence of change, as well as recognizing the diversity and apparent relatedness of species,
needs to be firmly established before delving into possible mechanisms for evolution. To better understand
natural selection students can survey the examples of artificial selection occurring today with common pets like
cats and dogs, or numerous agricultural products.

Science SCI.III.4.1 Grade: 2