Ch 6 Quiz Retake

Scientists before Darwin had proposed that living things could change over time. Why was Darwin’s theory of evolution more powerful and useful than the proposals of the other scientists?

• Darwin explained the mechanism by which evolution occurred.

• Darwin cited examples from nature that were based on observations.

• Darwin used logical reasoning to argue that living things could change.

• Darwin hypothesized that evidence from DNA and genes would explain how evolution occurs.

Answer explanation

Darwin's theory was more powerful because he explained the mechanism of natural selection, showing how evolution occurs, unlike earlier scientists who lacked a clear mechanism.

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-4

Darwin collected and studied a variety of fossils. The fossils provided clues to ancient organisms. As Darwin concluded, how did ancient organisms compare to modern species?

• The ancient organisms were identical to modern species.

• The ancient organisms were larger or smaller than modern species, but otherwise identical.

• The ancient organisms were similar to modern species, but differed in several ways.

• The ancient organisms were very different from modern species, and lacked any significant similarities.

Answer explanation

Darwin found that ancient organisms were not identical to modern species; instead, they shared similarities but also had distinct differences, indicating evolutionary changes over time.

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-1

Artificial selection has produced a wide variety of crop plants, livestock, and pets. Which characteristic of artificial selection makes it different from natural selection?

• Humans, not the environment, select which organisms survive and reproduce.

• Adaptations develop gradually over many generations.

• The stock that are reproduced are genetically identical.

• All offspring are allowed to survive and reproduce.

Answer explanation

Artificial selection differs from natural selection because it is humans who choose which organisms survive and reproduce, rather than the environment making those decisions.

The adaptations of a pelican include its long, pouch-like beak. Why is the beak of the pelican an example of an adaptation?

• The beak is a unique feature that is found only in pelicans.

• All birds have beaks, but the beaks vary among different species.

• The shape and structure of the beak have remained the same over many generations.

• The shape and structure of the beak are inherited and help the pelican survive in its environment.

Answer explanation

The correct choice highlights that the pelican's beak shape and structure are inherited traits that enhance its survival by aiding in feeding, demonstrating a clear adaptation to its environment.

Tags

NGSS.MS-LS1-5

Edwin is studying a population of rabbits in the neighborhood that surrounds his home. He observes a variety of fur colors among the rabbits, including gray, white, and brown. The rabbit fur also has a variety of markings, including spots and bands. Edwin argues that natural selection will occur on the rabbit population. It will result in a change in the distribution of fur colors and markings. Which observation would provide the STRONGEST evidence in support of Edwin’s argument?

• Neighborhood plants can support a large increase in the rabbit population.

• Fur color and markings do not affect the running speed of a rabbit.

• A new predator tends to hunt more white rabbits than gray or brown rabbits.

• Most of the rabbits are wildlife, while some are pets.

Answer explanation

The strongest evidence for natural selection is that a new predator hunts more white rabbits, suggesting that white fur is less advantageous for survival. This would lead to a change in the distribution of fur colors over time.

Tags

NGSS.MS-LS4-4

NGSS.MS-LS2-4

The wing of a bird and the front limb of a mammal have a similar number and arrangement of bones. Which evolutionary relationship explains these similarities?

• The wing and front limb are homologous structures; each evolved from a common ancestor.

• The wing and front limb are analogous structures; each evolved from a common ancestor.

• The wing and front limb are analogous structures; each evolved independently.

• The wing and front limb are vestigial structures; one evolved from the other.

Answer explanation

The wing and front limb are homologous structures because they share a similar bone arrangement due to evolving from a common ancestor, despite serving different functions in birds and mammals.

Tags

NGSS.MS-LS4-2

The wings of ostriches are examples of vestigial structures. The wings provide evidence for which of these evolutionary relationships?

• A new bird species without wings will evolve from ostriches.

• A new bird species that has useful wings will evolve from ostriches.

• An ancestor of ostriches had useful wings.

• An ancestor of ostriches had vestigial structures.

Answer explanation

The wings of ostriches are vestigial, indicating that their ancestors had functional wings. This supports the idea that an ancestor of ostriches had useful wings, which is the correct evolutionary relationship.

Tags

NGSS.MS-LS4-2

A variety of plants and animals live in a meadow ecosystem. According to Darwin’s ideas about evolution, which of these meadow organisms has the greatest fitness?

• a snake that eats many mice, and then is eaten by a hawk

• a large, healthy hawk that does not find a mate

• a female mouse that has many offspring

• a lone tree that grows in the middle of the meadow

Answer explanation

According to Darwin's theory, fitness is measured by an organism's ability to reproduce. The female mouse that has many offspring demonstrates the greatest fitness, as she contributes more to the next generation.

Tags

NGSS.MS-LS4-4

Charles Darwin applied a wide variety of observations to help him develop his ideas about evolution. Which general statement describes several of the observations that Darwin made and considered, and later incorporated into his Theory of Evolution?

• Species may vary from place to place, but most species are distributed widely on all continents.

• Fossils show that ancient species were identical or nearly identical to modern species.

• All species use DNA to carry and translate genetic information.

• Species on islands tend to resemble mainland species, yet differ from them in many ways.

Answer explanation

Darwin observed that species on islands often resemble those on the mainland but have unique adaptations. This variation supports his idea of evolution through natural selection, making this statement the most relevant to his theory.

Giraffes, camels, and horses share some traits, although they vary in other traits. Which statement accurately describes the evolution of these species?

• Each species descended from an ancient common ancestor.

• All three species evolved from three unrelated ancient ancestors.

• Each species evolved uniquely, without any ancestors.

• Two of the species descended from the other species.

Answer explanation

Giraffes, camels, and horses share a common evolutionary ancestor, which explains their shared traits. This means they evolved from a single lineage rather than from unrelated ancestors or without any ancestors.

Tags

NGSS.MS-LS4-2