Answer to Question 1
Some psychologists have speculated that decreases in the amount of animal research has resulted, in part, from a change in theoretical perspectives, from behaviorism to cognitivism. Behaviorists were willing to generalize to people from animals, cognitive psychologists less so.
A second reason is that psychologists have turned their attention to different research questions, ones that are less likely to be answered through animal research. Part of this may be due to the increasing number of women in psychology.
A third reason is that people, including psychologists, are more sensitive to the ethical issues associated with animal research.
Answer to Question 2
Goldenberg et al. (1999) used a manipulated variable, whether participants were primed to think of sex or not by the content of a questionnaire. The researchers also identified the level of neuroticism, high or low, in their participants, a measured or quasi-experimental variable.
The investigators found that when the participants saw a group of letters and were asked to filling more letters to create a word (e.g., COFF _ _), the participants in the high neuroticism group were more likely to create a death-related word. If neurotic participants focused on romantic aspects of sex rather than purely physical aspects, they tend to stay away from death-related words.
Territory sizes differ among animals.
Enzyme activity is affected substantially by temperature
Arabidopsis plant growth is affected by touch.
Adolescents are preoccupied with finding their place in the social group as well as society.
Organ systems affected by cystic fibrosis