The sophisticated filtration system of giant manta rays might be the key to ridding the ocean of trash in the future.
In a new study, scientists looked at the marine animal's liquid-solid filtration system which can separate large volumes of particles such as tiny planktons and small fishes from water. The team recreated physical modeling of a manta ray's gill raker to simulate how manta rays separate solid and liquid particles that allow high flow rates and with no clogging.
The study was published in the journal Science Advances.
Manta Ray Filtration
Giant manta rays, unlike other predators in the sea, do not chase their preys. Instead, they capture huge amounts of water, trapping planktons, as well as small fishes and other crustaceans, into their mouths.
People assumed that manta ray gills function similar to a pasta colander; particles remain inside while the water drains out of its holes. However, Raj Divi, a biology graduate student from Cal State Fullerton, found that that is not the case. The filter of manta rays is a lot more sophisticated than initially imagined.
"Our study results show that manta rays do something really tricky. They create what we have termed a 'ricochet filter' to separate food from water," explained Misty Paig-Tran, faculty research adviser. "Particles enter into the mouth, then ricochet off the filter surface and back toward the esophagus, while water takes a different path and exits out the gill slits."
Perhaps more impressively, manta ray filters can spot particles that are much smaller than its pores.
"Although implementations vary widely, almost all filtration systems are based on a couple of fundamental separation mechanisms, such as sieve, cross-flow, hydrosol and cyclonic separation," she added. "Manta rays, on the other hand, have a highly specialized filter-feeding apparatus that does not resemble these filtration systems."
The researchers hope that the study will be used to create an efficient filtration system that can be used to filter particle-filled water, especially in remote areas that do not have access to clean drinking water.
Cleaning Out Microplastics In Water
Divi also hopes that the study can inspire new technologies to clean trash, specifically microplastics, in the oceans.
Studies show that microplastics are the most prevalent type of marine debris in oceans and great lakes. They come from a variety of sources, including larger plastic garbage that gets torn apart into smaller pieces.
An infamous type of microplastic is microbeads, which are primarily used in beauty products such as toothpaste and cleansers.
The National Oceanic and Atmospheric Administration said that microplastics pose a threat to life underwater.
