UM graduate student Phred Benham studies adaptations to living in salt marshes

savannah sparrow

Fig. 1. Savannah Sparrow

Phred studies adaptation to life in salt marshes. At high tide salt marshes get flooded with seawater making it a tough place to live. The Savannah Sparrow (see picture) is a species found in grasslands around Missoula, but they are also known to live in salt marshes. Unlike most animals they are able to drink seawater. A lot of the adaptations to salt marshes can be studied with museum specimens including increases in bill size and darker plumage. Phred’s research also looks at kidney morphology in Savannah Sparrow specimens that are now at the Philip L. Wright Museum. Kidneys help most mammals (including humans) and birds process the fluids in our bodies. In particular, it is important for us to keep the levels of salts in our body at a certain level, too low or too high can cause severe health problems. Bigger kidneys help Savannah Sparrows survive in salt marshes by helping the birds get rid of salts from their body after drinking seawater. Similar adaptations are found in desert animals like Kangaroo rats, which have larger kidneys to help conserve water.