Investigation Question:  What are some ways that organisms can be similar or different?

Investigation Question:  How can we describe the traits of organisms in a species?

Key Concepts:

1. Organisms have observable traits.

2. Organisms in a species have many similar traits, but for each trait there can be variation. 

Chapter Overview: 

In Chapter 1, students investigate why the wolves in the Elk Mountain Pack in Graystone National Park have different traits even though they are all wolves. Students learn that they will take on the role of wildlife biologists working to understand why one wolf, Wolf 44, looks different from the others in its pack. The unit begins with students observing similarities and differences in traits among different organisms. Students discover that every organism on Earth is related, but some organisms are more closely related than others. A series of activities, including working with a digital model, in which students observe similarities and differences in traits between increasingly closely related organisms introduces students to the concept that organisms in a species have similar traits, but there is also variation in those traits. Students observe and reflect on their own traits as humans through a Class Traits Poster Walk. Students are introduced to the features of a scientific explanation and, as a class, compose a scientific explanation that addresses the Chapter 1 Question: Why are wolves different even though they are all the same species? The purpose of this chapter is to introduce students to the concept of species and to provide opportunities for students to observe variation among organisms within a species. 

Investigation Question 1:  Why do only some organisms of the same species have similar traits?

Investigation Question 2:  Why do offspring have similar traits to their parents but not always to each other?

Key Concepts:

1. Scientists ask questions they can investigate by making observations. 

2. Organisms can have traits that are similar to their parents’ traits.  

3. Offspring inherit instructions for each trait from both their parents. 

4. Offspring can inherit different instructions from their parents, so offspring may have different traits. 

Chapter Overview:

In Chapter 2, students are introduced to a second wolf pack in Graystone National Park, the Bison Valley Pack. Students observe that Wolf 44 has a similar fur color to the Bison Valley Pack, even though it lives with the Elk Mountain Pack. In order to make sense of this, students begin to investigate where organisms get their traits. Like scientists in the field, students observe fruit fly parents and offspring as they look for patterns in the fruit flies’ traits. Students learn that genes provide the instructions for traits and that genes are inherited by offspring from both their parents. Students use a digital modeling tool to observe inherited traits in deer. Through these experiences, students come to an understanding that siblings may inherit different instructions from the same parents, causing them to have different traits. Students then apply their understanding of traits and inheritance to make sense of the patterns they observe in the traits of wolf parents and offspring. After considering additional features of a scientific explanation, students write their own scientific explanations that address the Chapter 2 Question: Why is Wolf 44’s color similar to one pack but different from the other? 

Investigation Question:  Can the environment affect inherited traits?

Key Concepts:

1. Some traits result from the environment. 

2. Organisms stay in groups in order to obtain food and meet their needs. The number of organisms in a group varies. 

3. Some traits result from both inheritance and interaction with the environment.  

Chapter Overview:

In Chapter 3, students investigate why Wolf 44 has traits that are different from its parents. At the beginning of the chapter, students start their investigation by asking questions and reviewing data about flamingo families. A pattern begins to emerge—students observe that feather color in flamingos seems to be associated with a flamingo’s environment. Students learn that an organism’s traits can come from the environment. Students use what they have learned so far about the influence of the environment on traits to write scientific explanations about where Wolf 44’s trait for hunting style came from. Students return to the class traits posters and consider factors that may have determined their own traits, leading them to identify some traits that are affected by inheritance and the environment. Students gather evidence for this idea by conducting a hands-on investigation of an inherited trait (the green color of celery) that can be affected by the environment (food coloring and water). Students then write their final scientific explanations of the unit independently, explaining how Wolf 44 came to be the medium size it is. 

Investigation Question:  N/A

Key Concepts:

1. Scientists can investigate questions by looking for patterns in data. 

Chapter Overview:

In Chapter 4, students apply what they have learned by engaging in investigations with data about another species found in Graystone National Park: White-Crowned Sparrows. Students are tasked with applying their understanding of where traits can come from in order to describe the possible traits that the offspring of one set of sparrow parents will have. Students ask questions they can investigate about the traits of the White-Crowned Sparrows and analyze data about sparrow parents and offspring to investigate their questions. This chapter culminates with students describing the traits the sparrow offspring could have and supporting their ideas with evidence.