Microbes and Plants - Freshwater Ecology: Concepts and Environmental Applications - page 139

Biography 8.1. RUTH PATRICK
Dr. Ruth Patrick (Fig. 8.7) is one of the leading diatom sys-
tematists in the world. She has used her taxonomic exper-
tise to extend the general theory of how aquatic microor-
ganisms colonize new habitats and for nearly 50 years has
assessed the condition of stream ecosystems from the struc-
ture of biological communities. Her publication list spans
62 years and includes 181 works, 143 as sole author and
38 as the first author; she is also coauthor of the authorita-
tive monograph on diatom systematics in North America.
Still active in her 80s, Patrick recently completed the third
topic of a series on rivers and estuaries. She has exhibited a continued dedication to
pollution control in aquatic systems, where she has pioneered the use of diatoms as
indicators of chronic pollution.
Patrick has served as president for major scientific societies and has served on
committees for several U.S. presidents, Congress, the National Academy of Sciences,
and others. Patrick was the recipient of the prestigious National Medal of Science,
conferred by President Clinton. This is added to a long list of awards that includes
25 honorary doctorates and election to the National Academy of Sciences.
Given the time period that her career spanned, she overcame tremendous ob-
stacles to become a leading scientist when women were not typically scientists, an
environmentalist when few were concerned about human impacts on the environ-
ment, and only the 12th woman in 100 years elected to the National Academy of
Sciences. A hallmark of Patrick's career has been her insistence on making a positive
difference. Her father, who allowed her to climb onto his lap to look through a mi-
croscope when she was 4 or 5 years old, guided her. Patrick notes that her father
would get up from the dinner table every night and say, “Remember, you must leave
this world a better place.” She has.

FIGURE 8.7

Ruth Patrick.

tozoa are only slightly larger than bacteria and can ingest virus-sized par-
ticles. The largest are visible to the unaided eye. This is a very diverse
group (Figs. 8.5D, 8.5E, 8.8A-8.8C, 8.9B, 8.9G, and 8.10), and includes
the most complex single-celled organisms known.
Life histories are generally simple. Sexual reproduction is widespread
but not universal. Many protozoa form cysts that are resistant to environ-
mental extremes. Other morphological variation among life cycle stages
can also occur, such as differentiation between forms that search for food
and those that consume it (Taylor and Sanders, 1991).
Various classifications of the protozoa have been proposed (Taylor and
Sanders, 1991), and molecular analyses indicate that there should be sev-
eral phyla of protozoa (Fig. 7.1). Members of the protozoa include organ-
isms from the entire lower portion of the Eukarya part of the phylogenetic
tree. A more traditional approach will be taken here, with protozoa in the
phylum Sarcomastigophora. The flagellates (those with few flagella) are as-
signed to the subphylum Mastigophora, which includes the photosynthetic