Forams don’t just record the climate. They can also take care of it (and thank God, since humans need all the help we can get).
Their shells are the key. Hönisch said there are hundreds of meters of sediments on the seafloor, and most of them are made up of forams’ fossil calcium carbonate shells. When you bring a lot of acidic seawater down to the bottom of the ocean, Hönisch said, you can neutralize the acidity of that water by dissolving these calcium carbonate shells.
“Having them in the ocean actually allows us to buffer climate change,” Hönisch said, adding, “So, they’re really helping us, they’re helping the planet reduce the climate swings that we’re seeing.”
That’s not all they do, though (which kind of makes me feel like an underachiever). Lam explained that scientists use benthic forams as biomonitors of pollution. Several species of benthic forams live in shallow marine and brackish water environments close to the coast, which are areas significantly affected by terrestrial runoff. Lam said that a lot of this runoff contains pollution from industrial and municipal sources. To get a picture of the degree and severity of pollution in a region, scientists analyze the abundance of certain benthic species, their shell characteristics, and what species are present as well as what species are not.
“For example, there are some benthic species that absolutely love sewage, and will increase in numbers when there is plenty of it (sewage to them is food, except when there is too much pollution, such as heavy metals, in the sewage),” Lam said.
Heavy metal pollution actually causes adverse effects in benthic forams, Lam said. Scientists have found that their shells become small, exhibit stunted growth, and can become abnormally shaped.