Nudi Gal

Sunday, November 8, 2026

Synaptic Plasticity

There is a crazy big worm like thing digging a hole in the patio near my front door. I heard it! Then I looked and it is pretty grotesque. I have to find out what it is!

Bryan, Linda and I had a fascinating chat over breakfast.

Bryan used to have a side hustle where he collected sea hares. In particular, the Aplysia californica. I was so curious who was in the market to buy sea hares. They are pretty hard to keep in captivity, so I didn't think it would be aquarists.

It turns out, they needed them for research. What!?!?!

The research was being done in Marine Research Plymouth Alliance in England and Woods Hole Oceanographic Institution. The original work was done on squids, but also on the sea hare.

Research was being done on their neurons. These animals are missing a myelin sheath which is a is a protective, fatty-protein layer that wraps around the long, threadlike part of a nerve cell called the axon. This means that the sea hare has very wide neurons making it very easy to see their nervous system. Researchers are able to put micro electrodes in and see how they are interconnected.

Researchers were able to train the neurons of sea hares. Similar to Pavlov's dogs, they used a rush of water followed by an electrical shock. When the sea hare learned that the water blast meant that a shock was coming, they would proactively retract their gills and mantle.

The researcher could see the neurons biochemical reactions to understand sea hare learning. It was an easy model to use leveraging fluorescent chemical nodules.

This was all happening in the 70s/80s/90s. Sea hares not being used in research as much as used to be.

Bryan would go collecting at low tide every couple weeks. He became really good at knowing exactly what to look for and would collect them by the hundreds. The researchers really wanted similar genetic makeup but it was difficult to breed and raise them in captivity. I have to ask him how much they cost per hare.

Here is a quick summary of the research:

The The Nobel Prize in Physiology or Medicine 2000 Press Release was awarded to Eric Kandel (along with Arvid Carlsson and Paul Greengard) for his research on the biological basis of memory and cellular learning using the sea hare (Aplysia californica), as detailed on Wikipedia: California sea hare.
Key Details of the Research
Subject: The California sea hare (Aplysia californica), a marine slug with exceptionally large, easily studied nerve cell bodies.
Discovery: Eric Kandel demonstrated that short-term and long-term memory formation in the sea hare occurs at the synapse (known as synaptic plasticity).
Broader Impact: He proved that the cellular and molecular mechanisms behind learning and memory in sea hares are fundamentally the same as those in mammals and humans.

I mentioned to Bryan that I want to go see Terry Gosliner do nudibranch research at the Academy of Sciences near San Francisco, California. Bryan doesn't live too far from there and has a spare room... and is really interested in going too. What!!??! I need to work on planning this.

I spent a quiet morning working on my photos from yesterday and even took a nap before the afternoon dive.

I realized how easy they make things for us here. I literally rolled out of bed at 2pm and we left the dock at 2:30pm. My camera was all ready to go so it was on the boat. I just grabbed my torch and climbed on the boat. I barely got my wetsuit on in time to roll in. I mean, what is better than that?

The afternoon dive was loaded with critters. This is what Lembeh is all about. I got several more nudi species and saw some other cool things too. We were back by 4pm so we had a couple hours before leaving for Blackwater. I think I am going to be brave and change batteries on my torch and focus light in between dives tonight. Yikes!

I also ordered noodles for dinner between dives. Let's see how that turns out.

I changed the battery on my focus light during the surface interval and put them in backwards. So I did not have a focus light on this dive.

Bryan was still asleep on the boat when Linda and I left. I wonder how long they left him there.

There were cookies out for us after the blackwater dives. I went to shower and when I came back they were gone! Ugh. I was devastated. A banana for me. Then my pillow.

Slugs

21 - Doriprismatica atromarginata

22 - Facelinid sp.

23 - Pteraeolidia semperi

24 - Coryphellina sp.

25 - Thecacera pikachu

26 - Dermatobranchus rodmani

27 - Goniobranchus verrieri

28 - Phyllidiella pustulosa

29 - Phyllidiella fissurata

30 - Chelidonura varians

31 - Goniobranchus sp. (was G. reticulatus)

And now for the Blackwater finds (before and after ChatGPT)...

Saturday, November 7, 2026

PB & Banana

Because I slept so much yesterday, I got up and started drinking coffee and looking through my photos.

The schedule is so weird because we don't really do anything in the morning, then we dive at 2:30pm, 6pm and one more... probably at 8pm-ish. So there isn't really dinner when we get back. Just a sandwich. I am totally fine with that. Especially because Indonesia has the best bananas. And they have peanut butter and white bread, so viola... that's a great meal for me.

The afternoon dives could be good for my 60mm lens and my MiniFlash strobes but it's too much work (and room for error) to switch daily. I am going to dive with the 30mm lens and the Atom strobes in my afternoon dives. I feel like I need the practice anyway. I doubt I am going to pull out the diopter or snoot while I am here. I'll most likely save that until Alor. I mean, unless I get bored.

Our third diver Bryan showed up at breakfast. He is a really nice guy who was supposed to come on the Blackwater Cozumel week. We know many of the same people.

I tried to sleep late morning/early afternoon but I really couldn't do it. I hope I'm fine this afternoon and evening.

The afternoon dive was right next to a boat. I seem to remember diving it in 2017. It was messy down there and so many nudis... TWENTY distinct species and one I have never seen before! I found a black frogfish on my own too that I don't think anyone else saw.

Oh, and we had a blue ring octopus.

I did yearn for my 60 mm lens though. Everything I shot seemed far away and flat. I guess I could try to get more creative with the 30 mm but I didn't change my settings too much.

I came back from the afternoon dive and housekeeping still hadn't made up my room. I think Blackwater totally messes up their routine with both cleaning and meals. I'll ask.

Tonight there are two boats going out for blackwater. Our boat will be doing two dives. The other has some newbies and Clara who gets to cold to handle two dives... so they will only be doing one.

Sam confirmed: we will also be getting peanut butter sandwiches for dinner in between the two dives. I ordered mine with bananas and Linda got hers with jam. High class baby. I guess we can also get noodles if we get sick of peanut butter. But the bananas are so good here. I am fine with it.

For both blackwater dives, I had my own guide: Risman. He kept me busy.

Turns out, I only ate half of the PB & Banana sandwich. I just wasn't feeling all that hungry. During the surface interval I asked everyone where they went to their first concert. I got some good answers! Frank Sinatra. The Who. A festival in Leeds. And mine was INXS at The Meadowlands. Then I fell asleep as we were waiting to enter. Twice.

On the second blackwater dive, my focus light was running out of battery. That sucks. I either need to use the lesser setting or change batteries in between blackwater dives. I really don't want to do that!

Back to the purpose of this blog... the Nudi Count:

1 - Phyllidia varicosa