本题目来源于试卷: Continuity and Change D.11 Stability & Change，类别为 IB生物学
[问答题]
1.Outline the primary sodelg+,ea 3e+a)cj/i burclotr v:u39z*agwi ch7l,x ga;4q72yoes of variation in a species.
2.Describe the possible outcomes of a population producing more offspring than available resources can support.
3.John Endler carried out a series of experiments in the 1970s on the selection pressures that influenced the colour of guppy fish. State the independent variable in Endler’s experiments and explain the selective pressures exerted on male guppies.
| 
