n most populations of elephants, 100% of males and about 95% of females have tusks. Tusks are important for males in defense and displaying to potential mates. In several populations in Africa, the percentage of females without tusks increased during a period in which humans were hunting elephants in order to sell the ivory in their tusks. Which of the following statements about this phenomenon is TRUE?Question 3 options:A. In populations without hunting, individuals without tusks have lower fitness than those with tusks.B. Selection favoring females lacking tusks in these populations is due to the action of humans.C. Tusks are important for male mating success in these elephants.D. all of the above
Added by Julio R.
Step 1
** Show more…
Show all steps
Your feedback will help us improve your experience
Luke Humphrey and 58 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Luke H.
Use the theory of evolution to explain the observation that there are no tuskless males in the park. Why do males retain their tusks, when 50% of females lost them?
Adi S.
Most African elephants have tusks, but typically about 6% of females in a population will never grow tusks. Adult males are very rarely found without tusks. However, in Gorongosa National Park in Mozambique, 50% of females over 20 years old are tuskless, and 33% of females between 10 and 20 years old are tuskless. 1. What are tusks and how does an elephant use them? 2. What happened in Mozambique between 1977 and 1992? How did this event affect the elephant population? 3. What percent of the females in the population greater than 20 years old were tuskless? What percent of the females between 10-20 years old were tuskless? Explain the reason for this difference. 4. What percent of the males in the population were tuskless? Why is there a difference of tusklessness between males and females? 5. Is tusklessness an inherited or an acquired trait? Would tuskless females tend to have tusked or tuskless offspring? Explain. Part II: Evidence of Evolution by Natural Selection Listed below are four conditions of natural selection with a description of each. Using the trait of tusks vs. no tusks, provide evidence that the shift in frequency of the trait is a result of natural selection. (5 pts) Condition Description Evidence Variation Individuals in a population or group differ in some trait of interest. Inheritance The variation in the trait of interest is at least partially inherited (passed from parents to offspring). The variation stems from random mutations and accompanies sexual reproduction. The genetic variation may have arisen many generations in the past. Differential survival and reproduction More offspring are born than can survive, resulting in competition among individuals within a population. Some individuals with a particular trait are more likely to survive and/or have relatively more offspring compared to individuals that do not have that trait. Adaptation The frequency of the trait that helps individuals survive or leave more offspring will increase in the population over time, as will the frequency of the alleles that affect the trait. Part III: Current African Elephant Populations: Do your own research to determine how the African elephants are doing. What is the size of the population? What is their status? Are there any protections? etc. (5pts)
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
200,000+
Students learning Biology with Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD
