E. Grey Linsley

Foraminifera (forams for short) are single-celled organisms that live in sediment at the bottom of bodies of water. When they die, they leave behind fossilized records of their mineralized shells or organic linings that become preserved in layers of sediment. Due to their short lifespan (3 - 15 weeks), they are an essential tool for the reconstruction of paleo (over 2.5 million years ago) and environmental conditions. There are over 4,000 different species of forams, with abundant fossils dating back 540 million years. 

Unfortunately, records of organic linings from forams are very limited in quantity in contrast with the records from shelled forams, making it harder to trace their lineage. In part, this is due to the short life span of the organic lining, as it is composed of entirely organic matter. The dividing factor amongst forams is their shells: deep-sea forams have a hard calcium shell, whereas estuary and brackish water forams create their own shells from sediment and mineral flakes and occasionally from other forams. 

Some recently discovered estuary forams either don't make their shell (of mineral flakes, etc), or lose theirs, and instead develop veins of pyrite (fool’s gold) and a golden sheen between the chambers of their organic lining. This behavior is not normal for forams, and indicates that they are ill, or at the very least unwell. My project will aim to discover why these forams lose or don’t form their shell over their organic lining. My mentor and I suspect that it relates to water acidity abnormalities and levels of pollution. My project will examine the relationship among three primary factors: the number of forams per sample, their metal composition vs. organic composition, and an analysis of the types of metals in them. By understanding the underlying causes of the gold veins, we gain a better understanding of forams and can therefore create more accurate paleo climate reconstructions and future climate predictions.