For pond 1, the scientists noted: - a high tadpole density - a low amount of food - that most of the tadpoles counted were either detritus feeders or carnivores, with only a few intermediates. Describe and suggest reasons for the type of natural selection that seems to be operating in pond 1.
For pond 2, the scientists noted: - a low tadpole density - enough food for all tadpoles - that most of the tadpoles counted were intermediates, with fewer detritus feeders or carnivores. Describe and suggest reasons for the type of natural selection that seems to be operating in pond 2.
The intestine length of S. multiplicata tadpoles shows continuous variation. Sketch a curve on Fig. 7.2 to show how intestine length varies within the tadpole population in pond 2.
A student suggested that the variation in S. multiplicata tadpoles could result in sympatric speciation in some populations. Outline the features of sympatric speciation.
The intestine length of $S.\,multiplicata$ tadpoles shows continuous variation. Sketch a curve on Fig. 7.2 to show how intestine length varies in the tadpole population in pond 2.
A student suggested that the variation in $S.\,multiplicata$ tadpoles could result in sympatric speciation in some populations. Outline the features of sympatric speciation.
Fig. 7.3 shows the evolutionary relationships between three species of American spadefoot toad. Explain how analysis of DNA was used to determine the evolutionary relationships shown in Fig. 7.3.