Dots on a canvas

"White blob" in all its blob-ish glory

It's always a good day when data land in my inbox. Recently, I have been working to identify larvae and juvenile invertebrates that I collected on R/V Polarstern earlier this year. Some of you might remember that I used a fine mesh net on an epibenthic sledge to collect larvae in the Arctic deep sea. I also had the opportunity to collect larval traps I had left on the seafloor 5 years earlier. Needless to say, identifying larvae from the Arctic deep sea is a challenge. DNA sequencing is absolutely necessary for identifications. So when the sequences show up in my email, I get excited. 

My lab has refined a great protocol for DNA extraction and amplification for single larvae. It's working reliably now, even for some challenging specimens. This week, I was delighted to get successful sequences from my Polarstern samples. 

There were some surprises, to be sure. The biggest surprise was from a specimen I had named "white blob" on board the ship. To my shock and amazement, "white blob" actually gave me a decent sequence. It even matched to a few sequences in a public database. I concluded the "white blob" belonged to a segmented worm in the family Capitellidae. Cool!

Baby snails in the egg case I found

The other surprise had to do with snails. When I collected my 5-year experiment, I was ecstatic to find some snail egg cases on the plastic. They were in excellent shape and absolutely clear: I recognized them as snail egg cases immediately. My mind started racing. As far as I knew, there was only one snail in the Fram Strait: Mohnia mohni. Mohnia is a whelk, a predatory snail. The last time I encountered snail egg cases, they belonged to Urosalpinx cinerea, another predatory snail. Had I just found young Mohnia mohni? Does this common Arctic snail reproduce by laying egg cases? 

Not so fast, Kirstin. Don't jump to conclusions. 

I got a great sequence from the snail egg cases. And they're not Mohnia mohni. The snails actually belong to a group that I didn't even know was in the Fram Strait. The adult snails must be small enough that we don't see them with the towed camera. I was reminded of a study from a few years ago that showed you have to sample all life-history stages to truly understand the biodiversity of a region. By looking at the egg cases, I found a species that I didn't know was there. 

Sometimes, science comes together like a pointillist painting. Each sample is one dot on the canvas. Taken together, they show a beautiful picture of the world.