Explain why scientists use shared
characteristics to make cladograms.

Scientist use synapomophies, or shared derived characters, to define cladograms. For instance, mammary glands are a shared characteristic of mammals. All mammals and their oldest common ancestor, had or have mammary glands.Thus, if we are looking at an unidentified animal and trying to place it in a cladogram, if it has mammary glands we know it belongs in that branch. Cladogram is a diagram used to represent a hypothetical relationship between groups of animals, called a phylogeny. A cladogram is used by a scientist studying phylogenetic systematics to visualize the groups of organisms being compared, how they are related, and their most common ancestors.  

Explanation:

Sample Response: Shared characteristics are features or qualities that organisms have in common with each other. They are used to make cladograms because they show the relationships among organisms. They can also show which organisms have a common ancestor.

Explanation:

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.