Paleontologists did not just stumble across Tiktaalik. Instead, they formed a hypothesis about where they would find a transitional form between fish and tetrapods. What might have been the logical first step in deciding where to look for a transitional form between fish and tetrapods?

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.