Concept explainers
(a)
To infer:
About the relative costs and benefits of large brains documented in the fossil records of certain lineages of humans and other animals.
Concept introduction:
Animals with larger brain size are considered as more intelligent and hence they are more successful than animals with smaller brain size. The larger brain size can also help an animal in obtaining mates and therefore can increase their survival.
The larger brain size involves a higher cost, but it is outweighed by the survival benefits that an animal gets.
(b)
To hypothesize:
In what way the natural selection might have favored the evolution of large brains despite their high maintenance costs.
Concept introduction:
Animals with larger brain size are considered as more intelligent and hence they are more successful than animals with smaller brain size. The larger brain size can also help an animal in obtaining mates and therefore can increase their survival.
The larger brain size involves a higher cost, but it is outweighed by the survival benefits that an animal gets.
(c)
To graph:
The data for 14 bird species and conclude about the relationship between brain size and mortality.
Concept introduction:
Animals with larger brain size are considered as more intelligent and hence they are more successful than animals with smaller brain size. The larger brain size can also help an animal in obtaining mates and therefore can increase their survival.
The larger brain size involves a higher cost, but it is outweighed by the survival benefits that an animal gets.
Graphical representation:
The graph between the mortality rate and deviation of brain size from expected is shown below:
Graph 1: Relationship between the mortality rate and deviation of brain size from the expected value. The x-axis represents the deviation of brain size from expected and the y-axis represents the mortality rate.
Want to see the full answer?
Check out a sample textbook solutionChapter 27 Solutions
Campbell Biology in Focus, Books a la Carte Edition; Modified Mastering Biology with Pearson eText - ValuePack Access Card - for Campbell Biology in Focus (2nd Edition)
- Pakicetus is an ancient wolf-like organism that lived 50 million year ago. It had wolf-like ears and nostrils on the front of its skull. Modern whales have a similar ear structure, but their nostrils are on the back of their skull. Aetiocetus lived 25 million years ago, had the same ear structure as both Pakicetus and modern whales, but nostrils in the middle of its skull. According to this information, the most likely conclusion that biologists could draw about the relationship of Aetiocetus to the other organisms is that Aetiocetus...arrow_forwardExplain the difference between generalized and specialized characteristics. What are examples of each in terms of the adaptive potential? Define the term “adaptive radiation” and explain why it is important to the principle of evolution. Why was adaptive radiation especially important to mammals’ eventual rapid evolutionary success and diversification? What are some of the different groups of mammals?arrow_forwardA group of scientists examine the skeletal evidence below. Gibbon Orangutan Chimpanzee Gorilla Human What conclusion can be drawn from the diagram to support the theory of evolution? Man evolved from gorillas which evolved from chimpanzees. O Gibbons are most closely related to man because of similarities in their skeletal structure. O Orangutans have a larger jaw size than chimpanzees, allowing them to have a more carnivorous diet. Gorillas continued to walk on all four limbs to move around on the floor of forests, while man became bipedal to live in grasslands in order to hunt and carry food. O O O Oarrow_forward
- According to Lamarck’s theory of evolution, organisms change during their lifetime to survive then pass these changes to their offspring. What supports the hypothesis of Lamarck? a. Webbed toes of ducks to quickly move through the water, retractile claws of carnivorous mammals to catch the prey, millipede producing awful smell for self-defense and evolution of short-necked to long-necked giraffe b. Evolution of short-necked to long-necked giraffe, webbed toes of ducks to quickly move through the water, disappearance of limbs in snakes and retractile claws of carnivorous mammals to catch the prey c. Rattlesnake producing venom against predators, jellyfish bioluminescence for intraspecific communication chameleons camouflage to hide from predators and millipede producing awful smell for self-defense d. Disappearance of limbs in snakes, chameleons camouflage to hide from predators, evolution of short-necked to long-necked giraffe and rattlesnake…arrow_forwardA. According to Gould and Vrba (1982), when the original cooling function of insect appendages was changed to flying, this is an example of a. inheritance. b. exaptation. c. apatation. d. adaptation. B. When primates first evolved away from their mammalian ancestors, they a. developed a larger and more complex brain. b. increased their reliance on the sense of smell. c. increased the number of canines (for meat-eating). d. all of the abovearrow_forwardChanges in the traits of the fossils studied are consistent with what is expected to be favored by natural selection, given environmental changes during that time. Thus, from the late Miocene, modern horses evolved to have the following traits, consistent with grassland ecosystems becoming more common, EXCEPT for -- A. Formation of hooves and fused forelimb bones. B. Teeth adapted for browsing rather than grazing.. C. A muscle and tendon system allowing for a springing motion in galloping. D. Larger animals better designed for grazing.arrow_forward
- Pakicetus is an ancient wolf-like organism that lived 50 million year ago. It had wolf-like ears and nostrils on the front of its skull. Modem whales have a similar ear structure, but their nostrils are on the back of their skull. Aetiocetus lived 25 million years ago, had the same ear structure as both Pakicetus and modern whales, but nostrils in the middle of its skull. According to this information, the most likely concilusion that biologists could draw about the relationship of Aetiocetus to the other organisms is that Aetiocetus O evolved as whale ancestors lost their forward-placed nostrils through disuse. O is the ancestor of both Pakicetus and modern whales. O is not related to either Pakicetus or modern whales. O is a transitional form between Pakicetus and modern whales.arrow_forwardWhich of the following observations best supports the conclusion that two animal species evolved from a common ancestor in recent geological history? A The species are both herbivores. B The species have similar bone structure. C The species live in the same environment. D The species both obtain oxygen from the air. Choosearrow_forwardSome advocates of the view that all organisms were created simultaneously by God argue that vestigial structures do not constitute evidence of evolution, because they show only that a divinely created structure can degenerate over time. According to this view, human tailbones are not evidence of evolution because they do not show that an adaptive improvement has occurred. Is this a valid argument?arrow_forward
- Assume that you discovered Caenorhabditis elegans that crawl significantly slower than others. How would you determine whether this behavior was due to an injury from the environment or to an inherited trait? A goal of using animal models is to explain the molecular detail of specific behaviors encoded in the human brain. How would you compare the developmental biology experiments on memory and learning using the fruit fly, Drosophila melanogaster, as evidence about the evolution of a human behavior?arrow_forwardConsider the figure attached. A student in a course on intelligent design theory claims that the graph in part (a) shows that losing the ability to respire actually is adaptive for yeast cells living in small populations. Please read the incomplete sentence that appears immediately below, assess as possible completions the lowercase-Roman-numeral-labelled statements that follow, and click each uppercase-letter-labelled response that is presented below and completes accurately the sentence. An astute student in an evolution course would respond that i. the graph in part (a) shows that selection among mitochondria within yeast cells can lead to fixation for traits that decrease mean fitness for that yeast population. ii. the student in the course on intelligent design is wrong; the yeast cells in the small population group retained completely the ability to respire, as they otherwise would have been unable to harvest energy. iii. a property (e.g., inability to respire) that is…arrow_forwardYou are reading a scientific paper regarding the relationships of the anatomical and behavioral characteristics of chimpanzees and their implications for early hominid evolution. With the emphasis on anatomical and behavioral characteristics, this implies that the researchers are relying on A. Traditional classifications of chimpanzees and humans B. Nonevolutionary classifications of chimpanzees and humans C. An incorrect classification of human ancestors D. Cladistic classifications of chimpanzees and humansarrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education