3.4.3.2 Variation

Grade: 
3
Subject:
Science
Strand:
Life Science
Substrand:
Evolution in Living Systems
Standard 3.4.3.2

Offspring are generally similar to their parents, but may have variations that can be advantageous or disadvantageous in a particular environment.

Benchmark: 3.4.3.2.1 Inherited Similarities

Give examples of likenesses between adults and offspring in plants and animals that can be inherited or acquired.

For example: Collect samples or pictures that show similarities between adults and their young offspring.

Benchmark: 3.4.3.2.2 Differences & Survival

Give examples of differences among individuals that can sometimes give an individual an advantage in survival and reproduction.

Overview

Standard in Lay Terms 

MN Standard in Lay Terms

Plants and animals have characteristics that are similar to their parents.  Individual animal offspring of a single species can have differences, including observable characteristic such as coloration, body covering, size and strength that help them or hurt them in their environment.  Differences among individual plants include observable characteristics such as roots, stems, leaves/needles/scales, flowers, fruits and seeds, and responses to stimuli.

Big Ideas and Essential Understandings 

Big Idea

  • Plant and animal offspring inherit characteristics from both parents and also acquire physical and behavioral characteristics during their lifetimes.  These characteristics can help the plant or animal to survive and reproduce in their environment.

  • Differences among individual animals include observable characteristics
    such as coloration, body covering, size and strength and feeding behaviors,
    nesting and migration.
  • Differences among individual plants include observable characteristics such
    as roots, stems, leaves/needles/scales, flowers, fruits and seeds, and
    responses to stimuli.
  • Many external structures of plants and animals (e.g., cactus thorn, porcupine quill, crab shell, bear claw, and kangaroo pouch) serve important functions, and students in grade three will recognize many common examples through reading and observing examples from nature. (California Science Framework)

The Essentials

Funnytimes.com 

Benchmark Cluster 

3.4.3.2.1  Give examples of likenesses between adults and offspring in plants and animals that can be inherited or acquired.

3.4.3.2.2  Give examples of differences among individuals that can sometimes give an individual an advantage in survival and reproduction.

Correlations 

NSES Standards

Each plant or animal has different structures that serve different functions in growth, survival, and reproduction.  For example, humans have distinct body structures for walking, holding, seeing, and talking.

LIFE CYCLES OF ORGANISMS

  • Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying.  The details of this life cycle are different for different organisms.
  • Plants and animals closely resemble their parents.
  • Many characteristics of an organism are inherited from the parents of the organism, but other characteristics result from an individual's interactions with the environment.  Inherited characteristics include the color of flowers and the number of limbs of an animal.  Other features, such as the ability to ride a bicycle, are learned through interactions with the environment and cannot be passed on to the next generation.

AAAS Atlas

The Living Environment: Variation in Characteristics

  • Some likenesses between children and parents are inherited.  Other likenesses are learned.  5B/1
  • Offspring are very much, but not exactly, like their parents and like one another.

Benchmarks of Science Literacy

By the end of the 5th grade, students should know that:

By the end of the 5th grade, students should know that:

By the end of the 5th grade, students should know that:

Framework for K-12 Science Education

Many  characteristics of organisms  are inherited  from their parents.  Other  characteristics result from individuals’ interactions with the environment, which can range from diet to learning.  Many  characteristics involve both inheritance and environment. 5LS3.A

Organisms have characteristics that  can be similar or different. Young animals  are very much, but not exactly, like their parents  and also resemble other  animals  of the same kind. Plants also are very much, but not exactly, like their parents  and resemble other  plants  of the same kind. 2LS3.A

Sometimes the differences in characteristics between individuals  of the same species provide  advantages in surviving, finding mates, and reproducing.  5LS4.B

Common Core Standards

The College and Career Readiness Anchor Standards can be incorporated into this standard:

Text Types and Purposes

  1. Write arguments to support claims in an analysis of substantive topics or texts, using valid reasoning and relevant and sufficient evidence.  

Students can write about and justify why animal's characteristics in a species will give them an advantage over others. (Benchmark 3.4.3.2.2)

  1. Write informative/explanatory texts to examine and convey complex ideas and information clearly and accurately through the effective selection, organization, and analysis of content.

Students can journal about their prior knowledge of how offspring are similar to their parents. (Benchmark 3.4.3.2.1)

  1. Write narratives and other creative texts to develop real or imagined experiences or events using effective technique, well-chosen details, and well-structured event sequences.

Students can create and describe imaginary animals with specific traits that give them an advantage in survival.  (Benchmark 3.4.3.2.2)

Misconceptions

Student Misconceptions 
  • Elementary, middle and high school students all exhibit the idea that traits are inherited from only one of the parents and that certain traits only come from the mother or father.  Keeley, P. (2007) Uncovering Student Ideas in Science. Vol. 2, USA : NSTA Press. p.13.
  • When asked to explain how physical traits are passed from parents to offspring, some students believe that traits are inherited from only one of the parents (for example, the traits are inherited from the mother, because she gives birth or has most contact as children grow up; or the same-sex parent will be the determiner). Other students believe that certain characteristics are always inherited from the mother and others come from the father.  Some students believe in a "blending of characteristics."  It may not be until the end of 5th grade that some students can use arguments based on chance to predict the outcome of inherited characteristics of offspring from observing those characteristics in the parents.
  • Organism Traits Video Clip (Benchmark 3.4.3.2.1): This segment provides information about commonly held ideas that students have about why organisms have certain traits.  Even though the students are not always cooperative, attempts are made to get the students to explain and think about their understanding of heredity.

Vignette

It is springtime and Mr. Smith and his 3rd graders are ready board the bus to take a field trip to the Minnesota Zoo.  The zoo's Baby Farm Animals exhibit is just getting underway.  The students are armed with their science notebooks and digital cameras and their task is to observe baby animals and their parents.  In cooperative groups of three, students will take pictures of baby animals with their digital cameras and also sketch 2 - 4 of these animals in their science notebook.  They also must go on a hunt to see if they can find the baby animals' parents. 

As students are making observations, they notice that some animals look different than their parents.  Mr. Smith poses questions to his students to get them thinking about why that might be and how that might benefit them.  The following day when they return to school, students will pick one animal and fill out a Venn diagram identifying how the baby is similar and different to its parent.  Students will upload their pictures to Voicethread and record their group talking about how the baby animal is the same and different from the parent animal.  Mr. Smith will upload these Voicethreads to the class webpage to share with parents and community members.

 

Resources

Instructional Notes 

Instructional suggestions/options:

  • Access students' prior knowledge, through journaling or discussion to assess what they already know about parents and offspring, and similarities and differences in organisms. 
  • Provide opportunities for hands-on observations of plant and animal offspring.
  • Use graphic organizers to identify and classify traits, and compare similarities and differences.
  • The use of science notebooks is valuable for students to record and organize their observations of organisms.  Students should use their science notebook to make scientific drawings of organisms (both animal and plant).  They should make tables and graphs to compare and classify different organisms (e.g. seeds).  The science notebook is also an opportunity for students to record systematic data over time to use in their analysis of organisms and how they change from young to adult. Examples of science notebooks.
  • Suggestions on the use of science notebooks.
  • Because the child's world at grades K-4 is closely associated with the home, school, and immediate environment, the study of organisms should include observations and interactions within the natural world of the child.  The experiences and activities in grades K-4 provide a concrete foundation for the progressive development in the later grades of major biological concepts, such as evolution, heredity, the cell, the biosphere, interdependence, the behavior of organisms, and matter and energy in living systems. 
Instructional Resources 

Selected activities

Battle of the Beaks

In this lesson, students learn about adaptive advantage, based on beak function, by simulating birds competing for various foods. (3.4.3.2.2.)

Clipbirds

Students learn about variation, reproductive isolation, natural selection, and adaptation through this version of the bird beak activity.  May need to be modified for younger students.  (3.4.3.2.2)

Take a nature walk in the spring and take digital pictures of adult animals and/or their offspring.  (Benchmark 3.4.3.2.1)

Students will collect samples or pictures of plants and animals that show similarities between adults and their young offspring. (3.4.3.2.1)

Animal Adaptations (3.4.3.2.2)

Purpose: To expand students' knowledge of animal features and behaviors that can help or hinder their survival in a particular habitat.

Context: As students approach this Animal Adaptations lesson, bear in mind that, according to research, most lower elementary school students are still forming a basic understanding of how animals survive in their respective environments.  For example, many students understand a simple food link between two animals, but many still assume that animals are still independent of each other and depend on humans to provide food and shelter.  Some students are unaware that many animals struggle to obtain adequate amounts of their particular food(s) and cannot simply change their diets as other food becomes available.

Nature and Nurture (Naturewalk) (3.4.3.2.1)

Purpose: To develop an understanding of the role both nature and nurture play in determining an individual's traits.

Environments and Ecosystems (Benchmark 3.4.3.2.2)

Students explore the biosphere and its associated environments and ecosystems in the context of creating a model ecosystem, learning along the way about the animals and resources.  Students learn that animals, plants and other organisms have different physical characteristics that make them more adapted to a particular environment. However, different types of organisms can live together in similar environments.  Birds have hollow bones (making them lighter) and feathers that help them fly.  Large animals need support and bone structure to walk; as a result, they have backbones and legs. Still, both of these animals might live in a forest.  Some physical characteristics make an organism less adapted for other environments.  For example, whales have blubber so they can withstand cold temperatures and other mammals have thick fur, which protects them from the cold.  Because of these characteristics, these animals would not survive very well in a hot desert environment.  Also, some animals can adapt to changes in their environment by changing their physical characteristics or changing their surroundings

FOSS: Structures of Life

Investigation 2:  Parts 1-3 (pp. 8-22) GROWING FURTHER

  • Students examine germinated seeds to determine similarities and differences in the way the organisms grow.  They set up a hydroponic garden to observe the life cycle of a bean  plant.  (Fits with Benchmark 3.4.3.2.1)

Investigation 3: Part 1 (pp. 8-13) MEET THE CRAYFISH

  • Students observe and record some of the structures of a crustacean, the crayfish.  They establish a feeding and maintenance schedule for the organisms.  Students investigate crayfish behavior by creating an enriched crayfish habitat.  They map where the crayfish spend their time within their habitat.  Students investigate crayfish territorial behavior. (Fits with Benchmark 3.4.3.2.2)

Investigations 4 (Part 1, pp. 8-13) and 5 (Part 1, pp.8-12):  MEET THE LAND SNAIL or BESS BEETLES

  • Students become familiar with snail or beetle structures and behaviors and set up an appropriate habitat for the animals.  They compare the structures and behaviors of the snail (a gastropod) or the beetle (an insect) to the crayfish (a crustacean).  They investigate the pulling power of the organisms.  Students plan and conduct their own projects to find out more about the structure and function of animals. (Fits with Benchmark 3.4.3.2.2)

*Information about investigations and correlations can be found at the following links: 

New Vocabulary 

Vocabulary/Glossary:

(definitions taken from www.wordcentral.com)

Acquired traits: traits that are the result of a person's experiences in the world, but are not inherited or passed on the next generation (examples: acquired knowledge, amputation, tattoo, docked tail, leaf damage, disease).

Adapt: to change so as to fit a new or specific use or situation.

Adult: fully developed and mature.

Behavior: things that organisms do.

Characteristic: a special quality or appearance that makes an individual or group different from others.

Environment: the surroundings of a plant or animal.

Function: how a structure works or how it is used by an organism.

Habitat: where an organism naturally lives.

Inherited: to receive by genetic transmission.

Inherited traits: traits that are genetically inherited and passed from generation to generation.

Offspring: the young of an animal, or plant.

Organism: any living thing, including plants and animals.

Population: a group of one species of organism living in a particular area or habitat.

Reproduce: to produce new plants or new animals.

Structure: any identifiable part of an organism.

Young: being in the early stage of life, growth, or development.

Technology Connections 

Waiter

This is a game that allows students to identify various bird beak characteristics and how they are advantageous in birds' food choices. (Benchmark 3.4.3.2.2)

Avian Resurrection

This is a game that allows students to explore differences in bird characteristics that are advantageous in habitats and to create birds that will survive in various habitats. (Benchmark 3.4.3.2.2)

Read Write Think

Provides access to the highest quality practices in reading and language arts instruction by offering the very best in free materials, including graphic organizers appropriate for science instruction.

A VoiceThread

A collaborative, multimedia slide show that holds images, documents, and videos and allows people to navigate slides and leave comments in five ways: using voice (with a mic or telephone), text, audio file, or video (via a webcam). Share a VoiceThread with friends, students, and colleagues for them to record comments too.

Kidspiration

This software allows students to create graphic organizers and visual representations of ideas. 

References 

Additional resources or links:

Variations Game:

In this set of outdoor games, learners play the role of monkeys that are trying to get enough resources (food, shelter, and space) to survive.  They play several simple games which involve strength, quickness, coordination, intuition, and luck in order to acquire these resources.  The games focus attention on the participants' individual variations in these areas. (Benchmark 3.4.3.2.2) 

Changing Cicada (Benchmark 3.4.3.2.1) 

Purpose: To study how offspring are very much, but not exactly, like their parents in the context of the periodical cicadas.

Context: The arrival of the periodical cicadas in the spring of 2004 provides a good way to review with your students the concept of heredity and how offspring are very much, but not exactly, like their parents.  Making use of an interactive slide show, this lesson provides students with an opportunity to consider the concept of heredity in the context of the periodical cicadas.  It should probably be taught after you have already introduced this concept to students by having them consider organisms with which they are more familiar - like themselves, their classmates, and their pets.

Assessment

Assessment of Students

1. Which animal lives in water when very young and then lives on land as an adult? (Benchmark 3.4.3.2.1/ Level 3)

A.    

B.    

C.    

D.    

The correct answer is C.  Question taken from NAEP test.

2. Look at the pictures of deer below. (Benchmarks 3.4.3.2.1 and 3.4.3.2.2 /Level 5 Synthesis)

Software: Microsoft Office

A.  The deer in the pictures are numbered.  Put the number next to the name that identifies each deer.

Male deer (buck) ______________

Female deer (doe) ______________

Young deer (fawn) ______________

B. Look at picture 2.  Name one feature about the deer's body that helps it to survive.  Tell how the feature helps it to survive.  Look at picture 3.  Name one different feature about the deer's body that helps it to survive.  Tell how the feature helps it to survive.

Complete Student Responses below:

Key for #2. The deer in the pictures are numbered. Put the number next to the name that identifies each deer.

Scorer Comments:

Student response addresses all seven parts of the question correctly: identification of all three deer, features of the buck (antlers), and features of the fawn (ears), with explanations of how those features help them to survive.  The buck has antlers to keep away predatory animals; the fawn has ears to detect approaching enemies.

(Question taken from NAEP Test)

Assessment Probes

  • Is it Living?   Keely, P. (2004) Uncovering Student Ideas in Science. Vol. 1. USA: NSTA Press. pp. 123-130.
  • Habitat Change  Keeley, P. (2007) Uncovering Student Ideas in Science. Vol. 2.  USA : NSTA Press. pp. 143-148.

Habitat Change (Benchmark 3.4.3.2.2/Level 4 Analysis)

A small, short-furred, gray animal called a divo lives on an island.  This island is the only place on Earth where divos live.  The island habitat is warm and provides plenty of the divos' only food - tree ants.  The divos live high in the treetops, hidden from predators.

One year, the habitat experienced a drastic change that lasted for most of the year.  It became very cold and even snowed.  All of the ants died.  The trees lost their leaves, but plenty of seeds and dried leaves were on the ground.  Circle any of the things you think happened to most of the divos living on the island after their habitat changed.

A. The divos' fur grew longer and thicker.
B. The divos switched to eating seeds.
C. The divos dug holes to live under the leaves or beneath rocks.
D. The divos hibernated through the cold period until the habitat was warm again.
E. The divos died.

Explain your thinking. How did you decide what effect the change in habitat would have on most of the divos?

Answer: the best answer is E: The divos died. Most of the divos probably died because the physical structures, physiology, and behaviors they were born with no longer fit the changed environment.

Adaptation  Keely, P. (2009) Uncovering Student Ideas in Science. Vol. 4. USA: NSTA Press. pp. 113-118.

Adaptation (Benchmark 3.4.3.2.2/Level 4 Analysis) 

Three friends were arguing about what would happen if a population of rabbits from a warm, southern climate were moved to a cold, northern climate.  This is what they said:

Bernie: "I think all of the rabbits will try to adapt to the change."

Leo: "I think most of the rabbits will try to adapt to the change."

Phoebe: "I think few or none of the rabbits will try to adapt to the change."

Which person do you most agree with and why?  Explain your ideas about adaptation.

Answer: The best answer is Phoebe's: "I think few or none of the rabbits will try to adapt to the change."  The key word is "try."  Adaptation is not intentional.

Assessment of Teachers

Baby Mice  Keeley, P. (2007) Uncovering Student Ideas in Science. Vol. 2. USA: NSTA Press. pp. 129-135. (When used with elementary, substitute the word "characteristics" for "traits")

  • What are examples of likenesses between adults and offspring in plants and animals that can be inherited or acquired?
  • What differences among individuals can give them an advantage in survival and reproduction?  For example, variation in bird beaks and claws.

Differentiation

Struggling Learners 

Using inquiry circles, provide students with books such as The Ugly Duckling by Hans Christian Andersen and Are You My Mother? by P. D. Eastman.  Have students create questions and predictions throughout the read-aloud.  Discuss why the characters in the stories didn't fit in, in their surroundings.  Use the inheritance of characteristics to identify how the characters knew they had found their families.  Write a class book about an animal that tries to find its family by comparing characteristics.

English Language Learners 

In a small group, pair ELL students and give them pictures of adult organisms and their offspring.  Set a timer for one minute and have one partner talk about how the offspring is the same and different.  Switch partners and give the second partner one minute to share.  Provide linguistic support for different characteristics (webbed feet, quills) and sentence frames such as "The parent is different from the offspring because ______________" or "The parent has _____________ and the offspring has _________________" to aid students in their discussion.  (Benchmark 3.4.3.2.1)

Extending the Learning 

Students can be introduced to nature vs. nurture discussion (inherited vs. learned).  Make a list of traits that they have and have them decide if these are inherited traits or learned behavior. (Benchmark 3.4.3.2.1)

Multi-Cultural 

Show children and their parents from around the world.  Talk about how children are the same and different around the world.  Talk about what characteristics are the same and different about children around the world.  Introduce the idea of learned behavior and have students share how children's behavior is different around the world and why. (Benchmark 3.4.3.2.1)

Special Education 

Give students pictures of adult and offspring organisms (plants and animals).  Have students match the offspring to an adult.  Ask probing questions such as: Why did you put those two together?  How are they the same and different?  (Benchmark 3.4.3.2.1)

Parents/Admin

Classroom Observation 

Administrators

Administrators will see students working with both plants and animals.  Students should be making observations of the characteristics of adult organisms and their offspring in their habitats.  Students should also be observing, recording and discussing those characteristics of organisms that aid in their survival and reproduction. 

Parents 

Have children make a list of their characteristics (eye color, hair color, curled tongue, double jointed, good at drawing or sports, etc.) then take the list home and discuss with their parents who they inherited these traits from.