Slack (2003) compares three groups that conducted biological research at Yale during overlapping periods between 1910 and 1970. Yale proved important as a site for this research. The leaders of these groups were Ross Granville Harrison, Grace E. Pickford, and G. Evelyn Hutchinson, and their members included both graduate students and more experienced scientists. All produced innovative research, including the opening of new subfields in embryology, endocrinology, and ecology, respectively, over a long period of time. Harrison's group is shown to have been a classic research school; Pickford's and Hutchinson's were not. Pickford's group was successful in spite of her lack of departmental or institutional position or power. Hutchinson and his graduate and postgraduate students were extremely productive, but in diverse areas of ecology rather than one focused area of research or the use of one set of research tools. Hutchinson's example shows that new models for research groups are needed, especially for those that include extensive field research.
What did Hutchinson's group research?
diverse areas of ecology

Bacteria display a wide diversity of shapes and sizes, called morphologies. Bacterial cells are about one-tenth the size of eukaryotic cells and are typically 0.5–5.0 micrometres in length. However, a few species are visible to the unaided eye — for example, Thiomargarita namibiensis is up to half a millimetre long and Epulopiscium fishelsoni reaches 0.7 mm. Among the smallest bacteria are members of the genus Mycoplasma, which measure only 0.3 micrometres, as small as the largest viruses. Some bacteria may be even smaller, but these ultramicrobacteria are not well-studied.
What is the common name for shapes and forms of bacteria?
morphologies

Chopin's public popularity as a virtuoso began to wane, as did the number of his pupils, and this, together with the political strife and instability of the time, caused him to struggle financially. In February 1848, with the cellist Auguste Franchomme, he gave his last Paris concert, which included three movements of the Cello Sonata Op. 65.
Plitical strife, popularity decline, instability of era and fewer students caused Chopin to what?
struggle financially.