Answer:
Option D, Number of limbs
Explanation:
Options for the question
a. Birth weight
b. Hair color
c. Number of offspring
d. Number of limbs
Solution
Variation within a species is caused due to genetic differences governed by varying allele frequencies and duet to environmental factors that somewhere effect the expression of the genetic potentials thereby causing phenotypic variation.
Number of limbs is a physical characteristics, very unlikely governed by genetic variation. While factors such as hair color (grey, black, white etc.), height (tall, short, medium) etc. are governed by genetic variation as a result of which they have several phenotypic variations.
Hence, option D is correct
C) According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, Giraffes with long necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring.
Microevolution includes evolution at the population and community level.
Answer:
A tick sucking a deer's blood
Explanation:
All other examples show mutualistic relationships - both species benefit from the relationship. With parasitism the one species benefits (the tick) while the other suffers (deer).
Answer:
D) A Survey of fellow classmates
Explanation:
This is the correct answer because an informal survey involves various answers that may or may not be accurate. Informal surveys cannot be held as scientific fact and are, therefore, not reliable. A scientific journal is reliable because it most likely includes data from an experiment and/or research of a trusted scientist or group. The results of past experiments are very reliable because these are the results of hard work and thorough planning and research. A scientific discussion with colleagues is not very credible because it involves the sharing of opinionated information, but it is certainly more reliable that the varying answers of school-aged peers.