The following 9 Anchor Papers represent a range of score points and are used in conjunction with the rubric to assess student responses.

Score for Anchor Paper #1: Rubric Score 1

Annotation: There is evidence in this response that the student has some understanding of the question. The student incorrectly identifies the process that led to the change (adaptation). The explanation for why the average beak thickness changed is overly general and vague (so it can eat its food). However, the student does correctly identify how beak thickness would have changed if the years 1986 to 1996 were wet years (birds beaks would get thinner because they would eat small seeds). The supporting details are only minimally effective. The use of accurate scientific terminology is not present in the response.

Score for Anchor Paper #2: Rubric Score 1

Annotation: There is evidence in this response that the student has some understanding of the question. The student briefly explains why average beak thickness changed between wet and dry years (when it was dry there were only large seeds to eat and that made their beaks thicker). The student also minimally addresses how beak thickness would have changed if the next ten years were wet years (beak thickness would decrease because there would be less large seed to eat). The process that led to this change is not named. The supporting details are only minimally effective.

Score for Anchor Paper #3: Rubric Score 2

Annotation: There is evidence in this response that the student has a basic understanding of the question. The student explains why average beak thickness changed between wet and dry years (because of the available food sources) with adequate supporting details (in the wet years there were more small seeds, so natural selection would have favored birds with thinner beaks because they could eat the smaller seeds; during the dry years, however, natural selection favored birds with thicker beaks because they could crack and eat the larger seeds). The student names the process (natural selection) that led to the change and briefly addresses the second part of the question (had the next ten years been wet years, the average beak thickness would dropped to much lower levels).

Score for Anchor Paper #4: Rubric Score 2

Annotation: There is evidence in this response that the student has a basic understanding of the question. The student explains why average beak thickness changed between wet and dry years (during the dry years, the birds must eat larger seeds, which require more force to crush, requiring a larger beak). The student also addresses how beak thickness would have changed if the next ten years were wet years (would become less thick; wouldn't need to crush large seeds; small ones would be more abundant). The student incorrectly identifies the process that led to the change (adaptation). However, the student uses adequate supporting details in an accurate description of what is actually the process of natural selection (single bird cannot change; population of birds shifts to having the most favorable traits because the organisms that are best suited usually live longer, producing more offspring).

Score for Anchor Paper #5: Rubric Score 2

Annotation: There is evidence in this response that the student has a basic understanding of the question. The student provides adequate supporting details to explain why average beak thickness changed between wet and dry years (in dry years, it is a favorable variation to possess thick beaks to crack the shells; wet years…a favorable variation…allowed for beaks that were not as thick). The student continues this discussion with how beak thickness would have changed if the next ten years were wet years (would steadily decrease). The student correctly identifies the process that led to this change (natural selection). More support would be needed for a higher score.

Score for Anchor Paper #6: Rubric Score 3

Annotation: There is evidence in this response that the student has a good understanding of the question. The student names the process leading to changes in beak thickness (natural selection) and explains it (an animal with desireable traits lives better and produces more offspring with those traits). The response shows some synthesis of information as the student provides an example by explaining why average beak thickness changed between wet and dry years (during the dry years the birds with thinner beaks....starve and can't get mates; larger birds…produce more offspring making a greater population of thick beaked birds). The student continues with how beak thickness would have changed if the next ten years were wet years (more birds with thinner beaks because they can eat the smaller seeds). Supporting details are generally complete. The use of accurate scientific terminology (trait; offspring; population) strengthens the response.

Score for Anchor Paper #7: Rubric Score 3

Annotation: There is evidence in this response that the student has a good understanding of the question. The student provides generally complete supporting details and shows some synthesis of information. The student explains why average beak thickness changed between wet and dry years (birds that survive are birds with thick beaks; thinner beaks are favored). The explanation of how beak thickness would have changed if the next ten years were wet years (frequency of the thin beak allele would raise in the bird population) is tied to the process (natural selection). The student provides more details (known as a directional shift because one allele is more fit to it's environment so there are more of that allele found), using scientific terminology (directional shift; allele) that strengthens the response.

Score for Anchor Paper #8: Rubric Score 4

Annotation: There is evidence in this response that the student has a full and complete understanding of the question. The student uses pertinent and complete supporting details that demonstrate an integration of ideas as the process (natural selection) is tied to the existing variation in the species (mutations, inheriting different alleles, or other factors produced variation in the bird's beak shape). The student explains why average beak thickness changed between wet and dry years (with more thin-beak birds surviving, more will grow old enough to reproduce, and the majority of the offspring will have thin beaks; birds with thick beaks…will survive and reproduce better). The explanation of how beak thickness would have changed if the next ten years were wet years (thin-beaks would repopulate; eventually almost all of the birds would be of the thin-beak variation) completes the response. The use of accurate scientific terminology throughout (mutations; alleles; variation; adapt) enhances the response.

Score for Anchor Paper #9: Rubric Score 4

Annotation: There is evidence in this response that the student has a full and complete understanding of the question. Using accurate scientific terminology, the student integrates pertinent details about natural selection (a higher fitness according to the current conditions would be selected for and have a better chance for survival; this organism would have ideal conditions and start reproducing; the organism with a higher fitness would make up the majority of the population) into the discussion of changes in the average beak thickness (as time goes on and the size of seeds changes the gene pool changes). The student also explains how beak thickness would have changed if the next ten years were wet years (natural selection…the majority of birds in that environment could posses a small beak until the conditions make seed size change). The further observation (natural selection…forms part of the evolution of species) helps to reflect a complete synthesis of information. The use of accurate scientific terminology (fitness; survival; organism; gene) enhances the response.

Additional Scored Student Responses