The authors review research on children’s reading motivation and its relation to their reading comprehension. They begin by discussing work on the development of school motivation in general and reading motivation in particular, reviewing work showing that many children’s reading motivation declines over the school years. Girls tend to have more positive motivation for reading than do boys, and there are ethnic differences in children’s reading motivation. Over the last 15 years researchers have identified in both laboratory and classroom-based research instructional practices that positively impact students’ reading motivation and ultimately their reading comprehension. There is a strong need for researchers to build on this work and develop and study in different age groups of children effective classroom-based reading motivation instructional programs for a variety of narrative and informational materials.

The role functionally redundant species play in ecosystem function has not been adequately investigated. To study this, we examined species richness and an ecosystem function, cellulose decomposition, while environmental conditions were held constant. Our hypotheses were (1) increasing species richness will have no effect on rates of cellulose decomposition and (2) species richness will decline over time in functionally redundant communities. A relatively simple microcosm-based system to manipulate complex microbial interactions was employed. Microcosms containing cellulose as the sole carbon source were inoculated at equal densities with none, one, two, four, or eight species of cellulolytic bacteria. At 5-d intervals for 25 d, community composition and cellulose decomposition were determined. We rejected both of our hypotheses. In a constant environment, greater species richness supported a greater number of individuals and subsequently greater rates of total cellulose decomposition. Furthermore, greater initial species richness maintained greater richness over time. These results provide experimental evidence that functionally redundant species may play an integral role in ecosystem function.

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