Opihi Limpets from Northwestern Hawaiian Islands

Who We Are

Christina Escobar

What We Did

Pif of Opihi Limpets

I spent three days in the Genetics 1-Selective Pressures lab where I helped Lauren and her team take measurements of the Opihi Limpets from the Northwestern Hawaiian Islands that Dr. Bird collected for their research. I took the measurements of at least 100 different sizes of shells from different locations on the islands shores. The size was labeled as A, B, C or D, depending on the shore height and the island it was taken from. I took the length, width, height (length-wise) and height (width-wise). I measured these with a tool called a Caliper.

I actually got to watch them test the DNA from these limpets in their test tubes. It was neat to see the actual “beads” of DNA in the tubes.

Lauren actually took me into the part of the lab and showed me an example of a DNA strand that was “good sample” and it was really neat to see.

What We Learned

I learned in this genetics lab that they are studying the growth of these Opihi Limpets, which are found on the coast of the Hawaiian islands, to determine if their environment effects the way they grow and if the types of predators effect them as well. Limpets are  little conical mollusks found clinging to sea rocks and shorelines. When the limpet is disturbed, opihi will clamp down hard and be difficult to dislodge from the rock. Algae is their main food source. Similar to other snails, an opihi is equipped with a broad muscular foot for clinging and crawling. It has tentacles, a head with eyes and a mouth at the end of a tubular structure called a proboscis. The opihi’s soft body mass is protected by a hard shell shaped like a cap. This low-profiled “cap” offers little resistance to water pouring over it. Grooves and ribs drain water down the sides of the shell, further protecting the inhabitant.

This genetics lab is actually taking the male and female parts out and separating them from the shell. They are extracting the DNA from the limpet’s actual body tissue and cutting down the DNA, so it can be easily tested. Once the DNA is done and put into a form that they want, the lab sends the DNA off to the sequencing center to get sequenced for further testing. The target DNA that this research protocol is shooting for is 350-750 BP, which is a smaller DNA sample.

Pic of Opihi limpets from hawaii

Questions We Have

The questions that I have are:

What exactly would cause the DNA to change? What kinds of environments change the way these animals grow? Is it the water pressure or pressures from the waves from the different types of sea levels?

Connections to Teaching

The connections to teaching I would consider are connecting this type of lab to not only a science experiment but also a math lesson as well. Measuring these limpet shells is a good way to practice using different tools for measurement (like the Caliper) and experimenting with different levels of measurement. As far as science goes, a lesson on the different types of limpets on the different types of shores and compare the predators that effect them. We could set up a KWL chart with what we know about limpets and what we want to know about them and what we learned about limpets from the coast of the Hawaiian islands.