How Trees Calm Us Down

by Paola Salomon

Roger Ulrich perceived a pattern among patients that were recovering from gallbladder surgery at a hospital in a suburban area of Pennsylvania. The patients whose rooms overlooked a green area with deciduous trees were being discharged a day sooner than those whose rooms were facing a wall. But how can the trees positively affect patients in a hospital by just looking at them? A psychology professor, Mac Berman, led the study with the help of researchers in the United States, Canada, and Australia. The study compares two large data sets from Toronto. “The first measures the distribution of green space, as determined from satellite imagery,” while the second “measures health, as assessed by a detailed survey of ninety-four thousand respondents.” These are results reported by Alex Hutchinson in a 2015 New Yorker piece. They showed that “an additional 10 trees on a given block corresponded to a one-per-cent increase in how healthy nearby residents felt.” The cost of planting new trees is high, yet it was estimated that people would feel seven years younger. Continue reading

Effects of Ant- Fruit Interactions Deforestation

by Maithili Joshi

Biodiversity within an ecosystem has mutualistic and symbiotic relationships within that environment. The results of deforestation can be dramatic to these relationships, especially in cases with frugivores. The relationships between frugivores and fallen fruit are what help disperse seeds across the forest floor, which also helps the process of germination. In this study, Bieber et al. (2014) analyzed the mutualistic interactions between ants and fallen fruit in São Paulo State, SE Brazil. The scientists were examining the difference in interactions between disturbed and undisturbed forests. They compared the richness of ants at each fruit, species density per station, frequency of specific ant groups, frequency of fruit and pulp removal, and distance of fruit removal. The study was conducted using four disturbed forests, and four undisturbed forest areas. In these areas, there were thirty sampling stations with synthetic fruit placed 10 m apart from each other to ensure independent discoveries. The fruit were placed on a white sheet of paper within a wire cage to ensure that vertebrates did not access the fruit at each sampling station. Continue reading