Robert Blake Reeves, professor emeritus of physiology and an activist in environmental organizations, died Jan. 31 of prostate cancer in his Amherst home. He was 70.

Known as Blake Reeves, he was born in Philadelphia. He received a bachelor's degree with high honors from Swarthmore College and a doctorate in physiology from Harvard University, where he was a junior fellow in the Society of Fellows.

A faculty member in the Department of Physiology and Biophysics for 28 years, he was an authority on the effect of temperature on acid-base regulation and the kinetics of red blood cell oxygen exchange.

He served on the editorial board of the Journal of Comparative Physiology B, Biochemical, Systemic and Environmental Physiology, and was the journal's American editor for many years.

After his retirement from UB in 1995, Reeves became involved in field botany.

He had co-founded the Niagara Group of the Sierra Club in 1967, and in recent years was committed to the work of the Nature Conservancy, for which he served as a trustee of the Western and Central New York Chapter.

In 1996, he was one of three opponents of logging in Allegany Park to receive Environmentalist of the Year honors from Environmental Advocates, a statewide organization.

He also served on the Erie County Environmental Management Council.