Mediterranean climates, such as the one that much of California experiences, are characterized by two distinct seasons: a mild, moderately wet season and a warm/hot dry season. In most of the state the majority of precipitation falls between Thanksgiving and Memorial Day, with very little in the other months. At this time of year the dry season is in full swing. I’ve heard of a few reasons why California is called the Golden State: (1) the Gold Rush that began in 1848; (2) the carpets of California poppies that blanket the state in the spring; and (3) the drying up of the summer grasses, which covers much of the state in a golden mantle dotted with oak trees.
We are definitely in the golden season now. We had a good, colorful spring with a banner crop of wildflowers, thanks to the El Niño rains, and it was green well into July. Given the drought, we hadn’t seen that much green in years. But now the annual vegetation has dried out and most of the state is on high alert for wildfire. Fire is a seasonal event in the arid west, and every year several thousand acres burn in California. July and August are the worst months.
This year the most devastating fire in my region of the state is the so-called Soberanes fire burning near Big Sur. As of today the fire has blazed for 23 days, scorched over 71,000 acres, and is 60% contained. Almost 60 homes have been lost and over 400 other structures are threatened, all because some idiot lit an illegal campfire. Up here in Santa Cruz we are over 60 miles away from the fire, but the entire region has been affected by the smoke. Until recently the typical summer onshore winds have blown most of the smoke eastward and while we’ve smelled smoke here we have been spared the worst of it. This satellite photo was taken two days after the fire started:
This morning when I woke up the smell of smoke seemed stronger. It was foggy, enough so that water had condensed on the ground and cars, but instead of smelling like ocean the fog smelled like fire. The sun came out for about an hour in the mid-afternoon, showing a sky that wasn’t as blue as it is when ordinary fog recedes. Air quality is pretty bad so I’ve been staying indoors with windows and doors closed.
Last week I was in the Lake Tahoe region, on a short vacation with my family in South Lake Tahoe. On our first day there we went on a short hike in the Angora Lakes area. Let me tell you, being at altitude makes a concussion headache worse–I had been weaning myself off the ibuprofen, but had to go back on the full doses for the handful of days we were at altitude.
On 27 June 2007 an illegal campfire ignited a wildfire that eventually burned 3100 acres and destroyed more than 300 homes and commercial structures in a populated area near South Lake Tahoe. The Angora fire was fully contained on 2 July and 100% controlled on 10 July.
On the hike out to Angora Lakes you see a few burnt trees off the trail, but don’t really get a feel for the scope of the area affected by the fire. So on our way out of the Tahoe basin we drove through one of the neighborhoods that had burnt. Almost 10 years after the fire now, all of the burnt homes have been either rebuilt or completely torn down. It was interesting to see that the fire’s damage had been spotty: in a neighborhood of mostly older houses there would be a couple scattered here and there that were obviously new construction, likely post-fire rebuilds.
In the years since the fire there has been a lot of restoration work in the Angora region:
Fire is, or used to be, a significant part of the ecology of much of the western United States. Some plants’ seeds require the heat of fire to germinate, and fire opens up the canopy to allow low-growing plants access to sunlight. When a fire burns through a wilderness region the clock is reset on ecological succession, allowing different species of plants to take their turn thriving in the habitat. We humans experience ecology as a snapshot in time, the duration of our own lifetimes. In the aftermath of a wildfire we have the opportunity to observe the early stages of succession that will likely result, decades down the road, in a mature forest. Even now, only nine years after the fire, it is clear that plants, especially grasses, have been thriving in areas that had been burnt down to charred soil. It will be interesting to watch how succession proceeds over the next several years.
The strongest El Niño event on record has now been declared officially ended. For the past year and a half or so El Niño and a separate oceanographic phenomenon known as ‘The Blob’ have been battling it out for supremacy over weather and productivity in the northeastern Pacific, particularly in the California Current Ecosystem. It seems that The Blob, an area of unusually warm water stretching across the north Pacific from Japan to North America, had been in effect since 2014, and the arrival of El Niño combined with it to further depress productivity along the west coast of North America.
I’ve been recording temperatures in my seawater table at the marine lab for many years now. It has been only in the last year or so that I’ve made a concerted effort to record the temperature every day, but in general I have temperature data for at least several days a month going back to 1994. This morning I thought it would be interesting to compare 2016 temperatures with last year’s elevated El Niño temperatures. These are the data from 1 January through 26 July of both years:
The data are discontinuous in both years, but there are a few things to note. In the winter and spring there isn’t much difference in temperature between 2015 and 2016. Things change in April, when the 2016 temperatures are higher than in 2015. The El Niño was still in effect this past spring, which is reflected in the water temperatures. In May things get interesting. Starting in about mid-May 2015, the water temperature rose up to 15°C and remained at least that high for the next few months, with a handful of recordings as high as 18-19°C (data not shown). So far in 2016, the temperature has not exceeded 16°C in my table, and since mid-May has been averaging in the 14-15°C range.
A difference of 2°C may not seem like a big deal at all. One of my goals this summer was to collect plankton samples periodically and see if I could detect any biological signs that El Niño was abating. Of course, those plans got waylaid by the accident; I haven’t looked at a plankton sample since 27 April 2016. On the other hand I did manage to get out into the intertidal a few times after the accident, and noticed some differences from last year:
Okenia rosacea, the pink slugs that were everywhere in the intertidal last year, were much less abundant and a lot smaller this year. Last year it seemed that everywhere I looked I saw what looked like blobs of pink bubble gum spattered all over the rocks, along with their egg masses. This year I’ve seen Okenia but they aren’t nearly as conspicuous as they were last year.
Same goes for the large sea hares, Aplysia californica. Last year they were big weighty animals, common enough to make it hard not to step on them, and their spaghetti-like egg masses were everywhere. Seriously, many of the sea hares last year were two or three times the volume of my cupped hands. I did see several of them at Franklin Point last week, but they were much smaller.
I don’t have any quantitative measures or species-specific observations, but the algae seem more lush this year. And judging by what has been washing up on the beaches, the diversity is up, too.
We’re in that time of the year when the good low tides disappear for a couple of months, so there won’t be any more tidepooling excursions for me until October. Given the non-functioning condition of my brain, it’s probably just as well. I hope that some time this fall I can do some real science again, as it would be very interesting to see first-hand how the biota responds to the end of El Niño. Brain health must come first, though. For the time being I will have to content myself with eavesdropping on science and doing the little bits that I can.
This week saw the last of the good morning low tides of 2016. By “good” I mean a minus tide that hits during daylight hours. There are two more minus tide series in August, with the lows occurring well before dawn. After that the next minus tides don’t happen until mid-October; these will be late in the afternoon so loss of daylight will be an issue. I wasn’t intemperate enough to risk the health of my concussed brain on this week’s low tides but did want to get out if possible. And I’m so glad I tried, because having been out on the past few days’ low tides I feel more myself than I have since the accident. My head hurts a little, but not nearly as much as it would have if I’d done any significant driving two weeks ago. And, I have pictures to share!
Wednesday 22 July 2016—Davenport Landing
I went up to the Landing to collect some animals that I’ll need for my Fall semester class. The full moon was still visible, as the sun hadn’t yet risen above the bluff.
A month after the summer solstice and the algae are still nice and lush. Here’s a nice combination of mostly reds and greens, with some brown kelp thrown into the mix. How many phyla can you spot?
One of the two local species of surfgrass, Phyllospadix torreyi, was blooming. A month ago I’d noticed the congeneric species P. scouleri blooming at Mitchell’s Cove. These surfgrasses are vascular plants rather than algae, and as such they reproduce the way the more familiar land plants do, by pollen transfer from male to female flowers.
In the case of these obligately marine surfgrasses, the pollen is carried by water rather than wind. Not having to attract the attention of animal pollinators, the flowers have not evolved elaborate morphology, color patterns, or nectar rewards. They actually don’t look like much more than swellings near the base of the leaves. Some day I’ll remember to take one of the flowers back to the lab and dissect it to see what it’s like on the inside.
Thursday 21 July 2016—Franklin Point
This was the day I was most worried about. The drive up to Franklin Point takes about 30 minutes, and I hadn’t driven that distance since the accident. To make things even scarier, I couldn’t find someone to go with me. In the end I decided to try getting up there and back on my own, figuring that if my head wasn’t happy with the driving I could always turn around and come home.
When I got there it was cold and very windy, and I was glad I’d worn an extra thermal layer. Up on the exposed coast it is often windy on the road but can be less windy below the bluff on the beach. Yesterday it was windy on the beach, too, more typical of an afternoon than a morning low tide. The wind rippled the surface of the tidepools, making visibility and picture-taking difficult. I tried and didn’t have much success.
Coming over the last dune down to the beach I noticed four or five gulls and a couple of turkey vultures milling about at the mid-tide line. Something must be dead, I figured. And yes, it was very dead.
During last year’s El Niño we saw lots of sea hares in the intertidal up and down the coast. And they were big, heavy football-sized monsters. Yesterday I saw many sea hares, but none of then were larger than my open hand and most were quite a bit smaller. Nor were there any egg masses on the rocks. This guy/gal combo (they’re both, remember?) was about 15 cm long.
By far the most unusual thing I’ve seen in the intertidal this year was a swarm of shrimpy crustaceans. Last year at about this time I witnessed a huge population of small sand crabs (Emerita analoga) in tidepools at Franklin Point. Yesterday the swarmers were swimmers, not burrowers. I think they had gotten trapped in this large pool by the receding tide. Not having any better idea of what they were, I’m going to say they were mysids. Mysids are quite commonly encountered in local plankton tows but I’d never seen them in the intertidal before.
My first, rather idiotic, thought was that these were krill. They’re about the same size as the krill species most common in Monterey Bay, so perhaps the thought wasn’t quite that idiotic. (but krill in the intertidal? yeah, that’s idiotic. although stranger things have happened and the animals is always right even when it does something that seems idiotic) However, it didn’t take me long to realize that these critters didn’t actually look like krill. They didn’t have the feathery gills under the thorax that krill have. I also noticed that some of them were brooding eggs in a ventral pouch on the thorax, making them members of the Peracarida. Okay, then. Definitely not krill, so maybe . . . mysids? They look like mysids and so far nobody has told me that they’re not mysids, so I’m going to call them mysids.
The sun came out as I finished up in the tidepools. I hiked back up the very steep sand dune and looked back at where I had come from. Wow. Talk about stunning vistas!
View of Franklin Point from atop the last (and steepest) sand dune. 21 July 2016
Friday 22 July 2016—Natural Bridges
Today was by far the best day this week for picture taking in the intertidal. However this post is getting long so I’m going to showcase the crabs I saw this morning.
Pachygrapsus crassipes is the common shore crab, ubiquitous in the intertidal and at the harbor. It lives in the mid-tide zone and hangs out among the mussels. It is a shy beast, not aggressive and is more likely to drop into the nearest pool if it detects movement nearby. However, if you sit still for only a few minutes, you’ll find yourself noticing many small crabs coming out to bask in the sun.
Here’s a little tidbit about crab biology. All crustaceans breathe with gills. Any gas exchange structure, even your own lungs, functions by providing a surface across which oxygen can diffuse from the surrounding medium into the animal’s blood. Aquatic animals breathe with gills (if they have any specialized gas exchange structures at all, that is) and air-breathing animals breathe with lungs.
These crabs are often seen out of the water, in the sun. How then, you may reasonably ask, do they breathe with gills? The answer is, they foam. They produce bubbles that keep the gills moist, allowing oxygen first to dissolve into a thin layer of water and then to diffuse into the blood. I’m not entirely certain exactly how the crab forms the foam, but suspect it has to do with manipulating a thin layer of secreted mucus to capture small air bubbles. You do see the crabs massaging the foam over their sides, where the openings to the branchial chambers are.
Hermit crabs are the undisputed clowns of the tidepools. Around here we have four species that are commonly seen in the intertidal, all in the genus Pagurus. Many other species in different genera can be seen subtidally.
The most easily identified hermit crab in these parts is, in my opinion, Pagurus samuelis. They have bright red unbanded antennae, and often have bright blue markings on their legs. This species usually inhabits the shells of the turban snail Tegula funebralis.
The other species that I saw today was the much smaller P. hirsutiusculus. The common name for this animal is “hairy hermit crab” but they don’t seem all that hairy to me. They may be found in small Tegula shells, but I most often see them in shells of smaller snails such as Olivella biplicata.
There’s another P. hirsutiusculus in that other Olivella shell in the right-side of the photo, but it did not want to have its picture taken.
All told it has been a very satisfying week. I may have overtaxed my concussed brain a little bit. My plan for the weekend is to revert back to the rest-and-do-nothing routine to let my brain recover. Totally worth it!
I sort of assume that people appreciate the importance of honey bees. And then, every so often I am forcibly reminded that, even in the fairly ecologically savvy city where I live, there are those who would rather destroy honey bees than live with them. Fortunately, sometimes I am also reminded of the resilience of honey bees and the remarkable ways that they have adapted to living with humans.
Case in point. About a year and a half ago one of my students told me about a colony of bees living in a eucalyptus tree in his neighborhood, on a corner two blocks from the ocean. I went to check it out, and indeed there were bees coming and going from a hole about 3 meters above the ground. They seemed to be perfectly happy in the tree, and I was happy to know that they were there. I looked in on them every once in a while and noticed that in the early fall the entrance to the colony had been sealed up with some gunk that looked like white foam.
Given the stresses on honey bees these days—pesticides, varroa mites and other parasites, as well as some of the practices of commercial beekeeping—one of the most valuable things a hobbyist beekeeper can come across is a locally adapted feral colony. Local adaptation means exactly what it sounds like: bees that have evolved to survive and thrive in the conditions of a particular area. They will have survived multiple winters and whatever parasite load comes along with the location. While there would be a change in the royal regime every 2-3 years on average, the lineage of queens would be producing viable, vigorous workers. Beekeepers want to know that alleles from these locally adapted feral colonies are in the gene pool in which our queens are mating. Most of us would love to catch a swarm thrown by one of these locally adapted colonies (we may have done that earlier this season, in fact).
Yesterday I got a third-hand phone call about a “swarm of bees in a tree in such-and-such a neighborhood” and did I want to capture them? Mid-July is late for swarms, and after the caller mentioned what street they were on I realized we were talking about the feral colony I’d kept an eye on for the past year. I went down and looked at the tree, and noticed that the bees were in the same tree but had moved within the tree.
There was zero activity around the 2015 entrance. The two entrances are less than a meter apart on the outside of the tree, but there is no way to know whether or not the internal cavities are connected. The absence of bees near the door they were using last year suggests that the spaces are not connected. I wish I had a fiber-optic camera, because I’d love to see what’s going on inside that tree.
What’s going on outside the tree is a lot of coming and going.
While the neighbors and I were watching all the coming and going, I got a little of the backstory of this colony. The neighbors next to the property where the feral colony lives told me that there have been bees in that grove of eucalyptus trees for the 15+ years they’ve lived in their house. Last year, when the bees were in the lower entrance to the colony, the owner of the house on the corner called in an exterminator to poison them. The bees died but the cavity in the tree still contained wax and honey, which would be very attractive to a swarm looking for a permanent address. It appears that the bees currently residing in the tree either found or made themselves a new door, which at some point in recent months had been sealed up with foam (the orange stuff). They chewed through the foam and are carrying on as if nothing had happened.
Why would somebody pay to have an exterminator poison a colony of honey bees that is posing no threat? The reason must be fear and ignorance. This colony is high enough that the bees’ flightline is well above head height, and I imagine most people walking right next to the tree don’t even realize that the bees are there. However, fear is a powerful motivator, with ignorance coming in as a close second. The property owners decided that the bees were either a nuisance or a danger, and had them dealt with accordingly. Their neighbors, on the other hand, are happy to know that the bees are there to pollinate their gardens. I’ve asked them to keep in touch and let me know if they see anything interesting happening at the tree, and they’ve agreed to let us put a bait hive out there next spring to see if we can catch a swarm from this locally adapted colony.
One potential problem is that at some point in the past year or so the interior of the tree has been poisoned at least once. I don’t know what poison was used (it might not be difficult to find out but at this point I don’t want to bother–concussion, remember?) or its half-life in honey and beeswax. It could be that the bees living in the tree now are doomed because they’ve been exposed to the pesticide, or that any swarms they throw contain contaminated bees. I will keep watching this colony, though, crossing my fingers that they can continue to thrive despite the unfortunate activities of their closest human neighbors.
Some friends have asked what it’s like to have a concussion, and how my recovery is going. I think it’s hard for them to understand why, almost six weeks after the accident, I’m still having so many problems. Since this is my first concussion I don’t really know what to expect, but having consulted with a neurologist last week I feel assured that my recovery is on the right track. As a reminder, on Saturday 21 May 2016 I was in a head-on collision; two days later I was diagnosed with a concussion. The CT scan showed no brain swelling or bleeding.
I decided to address the “What is it like?” questions by listing the common symptoms of concussion and describing how I am experiencing them.
Symptom 1 — Loss of consciousness. I did not lose consciousness at any time after the accident. I remember quite a lot of the accident itself, the arrival of the EMTs and ambulances, getting my vitals checked in the ambulance, and getting ourselves to the ER.
Symptom 2 — Headache. After the accident the worst pain I had was around my ribcage. Actually, everything hurt. I didn’t notice the headache as a separate pain until Sunday when I tried to grade my final exams. Since then the headache has been a more or less constant companion. It gets a lot worse when my brain has been overtaxed or overstimulated (more on that below). The headache doesn’t feel like a tension headache and it isn’t localized. It’s a dull diffuse pain that feels like my entire head is being squeezed under the skin. The best thing to do when the headache gets bad is to lie down and close my eyes. Looking at computer screens is very taxing on the brain, which is why it is taking me three days to write this post.
Symptom 3 — Amnesia, confusion. I didn’t have any amnesia right after the accident, and I passed all of the cognitive evaluation questions the EMTs asked me (“What day is it?” “Who is the President of the U.S.?” “How old are you?” etc.). I knew where I was and how I had gotten there.
Symptom 4 — Dizziness, vertigo, nausea. This has been strange. On Monday, two days after the accident, I started experiencing a bit of vertigo. I would move my head and it felt like the world was taking a while to catch up. Also, I could read printed words on paper, but when I tried to read my students’ hand-written answers on their final exams the words swam around on the page. I gave that up as a lost cause and went back to the ER. This general wooziness resulted in some mild nausea.
There was a very early morning almost four weeks after the accident when I woke up feeling seasick. I took an anti-nausea pill and went back to sleep, and when I woke up for real a few hours later I felt no seasickness at all.
Symptom 5 — Cognitive deficits. I have these in spades, although I don’t know if anybody else can tell. For the first couple of weeks after the accident my head felt very foggy and it was difficult to process information. I’d walk around with a nectarine in my hand wondering what I was supposed to do with it. Oh yeah, those want to be eaten. I couldn’t really type, either. I could, but letters would come out in strange orders, as though my typing were dyslexic. That has gotten better recently.
I’m still having trouble carrying on detailed conversations. I can think of the words I want to say but they don’t make it to my mouth. And it feels like it takes me a very long time to process an answer when somebody asks me a question. What do I want to eat for dinner? Um. . . .
And yet, occasionally I can act with my usual decisiveness. Sometimes I feel as though I have my act together, and at other times. . . I don’t even know what my act is supposed to be.
My internal clock, which normally does a pretty good job of keeping track of elapsed time, is all out of whack. As is my ability to judge how long it will take to do a given task. This is rather a drag, as I’m used to my brain acting as a clock I don’t have to look at to tell the time. I suppose part of this deficit is due to the fact that I’m not spending as much time outdoors as I normally would in the summer, so I’m missing time cues that I should be catching.
Symptom 6 — Sensitivity to light and sound. As of now, six weeks post-accident, this is the most severe of my symptoms. It takes surprisingly little visual or aural stimulus to completely overwhelm my brain. Crowds, movement, the clinking of silverware on plates in a crowded restaurant, loud music, children playing (I think it’s their high-pitched voices that do it)–all are hell to me right now. There is no such thing as background noise to a concussed brain. Every sound pushes to front and center, demanding attention and energy that my brain simply cannot give. My brain reacts by hurting and trying to withdraw my consciousness from my surroundings. I can cope in the short-term by closing my eyes to shut out all visual stimuli, but I can’t close my ears and there are some sounds that dig their way into my brain. A massive headache ensues.
Right now there are two major construction projects going on at the marine lab, which makes the lab a very unhealthy place for me to be during the week. Fortunately there’s no construction work on weekends, so I can retreat down there for an hour of peaceful time with my critters. But even the running water through the seawater system makes a lot of noise; I’d never paid much attention to it before, except to notice when it was suspiciously quiet in the wet labs, but now it can get to me. I find that I need to minimize my time at the marine lab, period.
Driving remains extremely difficult for me. I can drive myself to and from the marine lab, but that’s about it. And even doing that little amount of driving causes a headache and wipes me out for the rest of the day. I’m not having flashbacks any more (more about that below) but my heart jumps every time a white car unexpectedly catches my eye. Driving takes so much concentration that my brain just isn’t up to it. I’m also fairly certain that my brain function is compromised enough to have slowed my reaction time. All in all, I don’t feel anywhere near competent to get behind the wheel of a car and drive any longer than 10 minutes.
Symptom 7 — Sleep disturbances. Dealing with these has been very strange. I’ve been sleeping a lot. At the beginning of my recovery I was taking 3-5 short naps every day, as lying down and closing my eyes was the only way to rest my brain. As the recovery continues I’m now a teensy bit more able to deal with sight and sound, and am down to 1-2 naps a day. But I also sleep late in the morning, which is extremely unusual for me. The past few mornings I have been sleeping past 07:00; usually in mid-summer I’m up at first light, or earlier if there’s a low tide to be had. I assume all this sleep is what my brain needs to heal.
Every night since the accident I have had crazy, vivid dreams. Some of them are borderline lucid dreams, in which I know I’m dreaming. And then things get sort of meta, when I think “This is a really strange dream I’m having right now.”
Symptom 8 — Changes in appetite. I am constantly hungry. All the time.
Symptom 9 — Psychological difficulties.I am definitely more irritable than I was before the accident. The niceties of polite conversation feel like such a chore that they just don’t seem worthwhile. I never was good at making small talk; now I find that having to do so really taxes my brain and gives me a headache. In this particular regard it seems that my natural introversion has been augmented by the concussion.
I’ve also noticed that my language filter has deteriorated quite badly. It is much easier these days for f-bombs to escape before I can hold them back. Then again, maybe it has nothing to do with the concussion but is because I’ve been watching “Game of Thrones” and “Orange is the New Black.” Those shows will definitely increase one’s tolerance for f-bombs and c-bombs.
For about a week after the accident I had flashbacks that occurred randomly throughout the day. I’d feel my body tense up for no apparent reason, then expect to hear the sounds of the collision and explosion of the air bags. I still get that momentary tensing when a white car suddenly appears out of the left side of my field of vision (the car that hit us was a white Honda sedan). And I really don’t like being in a car. The flashbacks aren’t happening nearly as frequently now, though, and that’s a good thing.
Symptom 10 — Hallucinations. I don’t have either visual or auditory hallucinations, per se, but there is almost constantly a snippet of music running through my head. This isn’t all that unusual for me; I seem to be very susceptible to infection by earworms. Since the accident one piece that my subconsciousness is obsessed with is Tchaikovsky’s Capriccio Italien. Why? Who knows. It happens to be the first piece of classical music that I remember from childhood, and maybe that’s significant. Other random bits of music running through my head at any given moment are Christmas carols (“Good King Wenceslas”; “Il est né, le divin enfant”; “In dulci jubilo”), old folk tunes (“My darlin’ Clementine”), the “Et in terra pax” movement from Vivaldi’s Gloria, and lately the opening riff from The Fixx’s “Saved by Zero.” Is there rhyme or reason to any of this? Not that I can see.
One interesting thing that the neurologist told me was that with concussions, the severity of the symptoms doesn’t typically correlate with the prognosis for full recovery or the time it takes to reach full recovery. Very often, he said, patients who report very mild symptoms either take a long time to heal or don’t reach 100% recovery. Of course, this led me to ask whether my symptoms would be considered mild, moderate, or severe. He smiled and said that my symptoms are congruent with a full recovery, then warned that it will be a slow process. I shouldn’t be surprised if it takes several months or a year not to have any symptoms.
One good sign is that my condition has improved quite a bit since the accident. Now that it’s July I need to start working on my class for the fall semester. I’m going to be taking things very slowly and resting/napping as necessary. I will continue to minimize my social activities and very gradually re-enter the world as my brain allows. Although I miss the field activities I had planned to do this summer, I’m learning how to do nothing, which can be sort of rewarding in its own way.
A long time ago in a galaxy called the Milky Way, a great adventure took place. We don’t know exactly when it happened, but it must have been very shortly after the evolution of the first cells. Some small prokaryotic cell walled itself off from its surroundings. Then it learned how to replicate itself and as cells continued to divide they began interacting with clones of themselves. Sooner or later, however, our clone of cells encountered cells from a different genetic lineage. These foreign cells were “other” and were recognized as such because they had a different set of markers on their outer covering. Perhaps there was an antagonistic interaction between the two clones of cells. In any case, this ability to distinguish between “self” and “non-self” was a crucial step in the evolution of life on Planet Earth.
The entire immune system in vertebrates is based on self/non-self recognition. It is why, for example, transplanted organs can be rejected by their new host–the host’s immune system detects the transplanted tissue as “non-self” and attacks it. As a result, patients who receive donor organs usually take immune-suppressing drugs for some period of time after the transplant.
The vertebrate immune system is quite complex and very interesting. It has two main components: (1) cell-mediated immunity, in which the major players are T cells; and (2) humoral (i.e. blood-based) immunity, which is the part of the immune system that produces antibodies to a pathogen when you get a vaccination. However, even animals much less structurally complex than vertebrates have some ability to recognize self from non-self.
Sponges, for example, exist as aggregations of cells rather than bodies with discrete tissues and organs. Most zoologists, myself included, consider sponges to be among the most ancient animal forms. They have different types of cells, many of which retain the ability to move around the body and change from one type to another; this totipotency is a feature that sponge cells share with the stem cells of vertebrates. There are sponges that you can push through a mesh and disarticulate into individual cells, and then watch as the cells re-aggregate into an intact, functioning body. As if that weren’t cool enough, if you take two different sponges and mush them into a common slurry, the cells from the distinct lineages re-aggregate with cells to which they are genetically identical. So even animals as primitive as sponges have some degree of self/non-self recognition.
If you’re lucky, you can see self/non-self recognition and aggression in the intertidal. Here in northern California we have four species of sea anemones in the genus Anthopleura:
Anthopleura xanthogrammica, the giant green anemone
Anthopleura sola, the sunburst anemone
Anthopleura elegantissima, the cloning anemone
Anthopleura artemisia, the moonglow anemone (and my favorite)
Of these species, only A. elegantissima clones. It does so by binary fission, which means that the animals rip themselves in half.
It looks painful, doesn’t it? As the two halves of the animal walk in opposite directions they pull apart until the tissue joining them stretches and eventually rips. Then each half heals the wound and carries on as if nothing had happened. Each anemone is now a physiologically and ecologically independent animal, and can go on to divide itself. And so on ad infinitum. The logical consequence of all this replication is a clone of genetically identical anemones spreading over a rocky surface. And that’s exactly what you get:
Okay, it’s hard to tell that these are sea anemones, but this is what they look like when the tide goes out and leaves them emersed. They pull in their tentacles, close off the oral disc, and cover themselves with sand grains. They look like sand but feel squishy and will squirt water if you step on them. In this photo, each anemone is probably 4-5 cm in diameter.
There are three patches of anemones in the photo above, separated by narrow strips of real estate where there are no anemones. Each patch is a clone, essentially a single genotype divided amongst many individual bodies. The anemones in each clone pack tightly together because they are all “self.” However, they recognize the anemones of an adjacent patch as “non-self” and they won’t tolerate the intrusion of neighbors onto their territory. Those strips of unoccupied (by anemones) rock are demilitarized zones. When the rock is submerged the anemones along the edges of the clones reach out their tentacles and sting their non-self neighbors. This mutual aggression maintains the DMZ and nobody gets to live there.
Because A. elegantissima lives relatively high in the intertidal the clonal patches are usually emersed when I go out to the tidepools. Its congener, A. sola, lives lower in the intertidal and is more often immersed at low tide. Anthopleura sola is larger than A. elegantissima and is aclonal, meaning that it does not divide. Anthopleura sola also displays quite dramatically what happens when anemones fight.
These two anemones, each about 12 cm in diameter, were living side-by-side in a tidepool. You can see that each animal has two kinds of tentacles: (1) the normal filiform feeding tentacles surrounding the oral disc; and (2) thicker, whitish club-shaped tentacles below the ring of feeding tentacles. These club-shaped tentacles are called acrorhagi, and are used only for fighting. The acrorhagi and the feeding tentacles may contain different types of stinging cells, reflecting their different functions. All tentacles are definitely not the same.
These animals, which represent different genotypes, are non-self to each other, so they fight. They inflate their acrorhagi, move their feeding tentacles out of the way, and reach across to sting each other. See how some of the acrorhagi on the animal on the right don’t have nice smooth tips? Those tips have been lost during battle with the animal on the left; the tips are torn off and remain behind to continue stinging the offender even after the tentacle itself has been withdrawn.
Here’s another picture of the same two anemones, taken from a different angle:
The goal of these fights is not to kill, but to drive the other away so that each anemone has its own space. Eventually one of them will retreat, and a more peaceful coexistence will be established. Fights like these have been going on for over half a billion years. Eat your heart out, George Lucas.
Every year, as early as Memorial Day or as late as Father’s Day, there’s about a week of really lovely low tides. This midsummer tide series usually includes the lowest low tides of the year, and we intertidal ecologists plan our field activities around them. Incidentally, there’s a corresponding low tide series in the midwinter, too. However, at that time of year the lows are in the afternoon, and because the low occurs about 50 minutes later each day you’re fighting darkness as you work the series. But in the summer, even if the first day of the tide series has a low tide before sunrise, that 50-minutes-later-each-day thing is really nice and you never have to worry about running out of daylight.
This year, the California Academy of Sciences sponsored several citizen science excursions called Bioblitzes to various locations on the California coast. The goal of these Bioblitzes was to document biodiversity in the intertidal in protected and non-protected areas of the coastline. Back in May I volunteered to lead a Bioblitz at one of the sites close to me, and planned to participate in a few others as well. In addition to actual organized Bioblitzes, citizens were invited to submit their own independent observations to the project.
Today is the three-week anniversary of the car accident that left me bruised and concussed. The bruises are pretty much healed at this point, and the soreness in my ribcage is also much improved. The medical advice I got for dealing with the concussion was, “Protect your brain from stimulation. Let it heal. And REST.” So for the past three weeks I haven’t been doing much of anything. I was worried that I wouldn’t be able to go out on any of the midsummer low tides, as it didn’t take much to overtax my injured brain and I didn’t want to risk overextending myself. I did end up skipping the first Bioblitz of the week and modified my original plans for the rest of the tide series to play it safe and stay closer to home.
I’m still trying not to spend too much time on the computer (electronic screens are very bad for injured brains) so I’m going to summarize my week’s activities in a single post. I’ll keep the stories short. But I did want to share some of the things I saw.
Day 1 – Natural Bridges, Monday 6 June 2016, low tide -1.6 ft at 06:25
My first venture out by myself was to Natural Bridges. It’s very close to my house and I figured that if I needed to bail I could walk out and be home within 15 minutes. It was cold and foggy and I felt energized just to be out there again.
Turns out this trip was about all my brain could cope with that early in the week. I skipped a Bioblitz up at Pigeon Point on Tuesday so I could stay home and rest, which ended up being a good call. A whole day of doing nothing was exactly what my concussed brain needed.
Day 2 – Mitchell’s Cove, Wednesday 8 June 2016, low tide -1.1 ft at 08:02
The day of rest was enough to get me back out there on Wednesday. My friend Brenna met me at Mitchell’s Cove for a morning of tidepooling. Mitchell’s Cove is a popular, dog-friendly beach in Santa Cruz, particularly busy in the mornings and evenings. Last September it was visited by a juvenile humpback whale, which came right into the Cove and hung out there for several days. I didn’t see any whales this week, but there was a surprising diversity of life in a relatively small area of rocky intertidal.
Phyllospadix scouleri, the species that has flatter, more ribbon-like leaves, was blooming. Its congener, P. torreyi, growing in almost exactly the same place, has narrow leaves that are more cylindrical in cross-section, and was not in bloom. Phyllospadix is a true marine plant; the flowers are inconspicuous swellings near the bottom of the leaves and the pollen is carried by water, rather than wind, to nearby plants.
And I saw two species of hydroids! This one is easy to ID to the genus Aglaophenia, but I would need to examine it under a microscope to determine the species. I wasn’t collecting anything on Wednesday so I don’t know which species it is.
And I saw an octopus! We know that they’re in the intertidal, but they are so cryptic and clever at hiding that we don’t see them very frequently. This one was definitely smarter than I was. Instead of scooping it out and placing it on dry ground so I could photograph it more easily, I chased it around a tidepool with my camera. Thus, this is the best picture I could get:
Day 3 – Davenport Landing, Thursday 9 June 2016, low tide -0.7 ft at 08:52
This was the day of my “official” Bioblitz. I had four participants–Brenna, Alice, Martha, and Andy. As of right now (Brenna hasn’t yet uploaded her observations) the other four of us have made 120 observations, documenting 50 species. Here are some of mine:
There are kelps, such as Egregia menziesii (feather boa kelp) whose habitat is the rocky intertidal. Most kelps, though, live subtidally, often in kelp forests. Nereocystis luetkeana, the bullwhip kelp, is one of the subtidal canopy-forming kelps. This one recruited to the intertidal. It is quite small and extremely cute; the float is only 2 cm in diameter.
Algae look their best when immersed. Out of the water they usually collapse into stringy or gooey masses, making it difficult to appreciate their structural beauty. This piece of Microcladia borealis was submerged in a tidepool, and fortunately there was enough light that I could take this picture.
Day 4 – Natural Bridges, Friday 10 June 2016, low tide -0.2 ft at 09:42
Yesterday I returned with a former student, Daniel, to Natural Bridges. It was sunny and warm, completely different from how it had been on Monday. There were many boaters out on the bay, taking advantage of the glassy flat sea.
I’ve seen a lot of shore crabs running around on the rocks this year. On cool, damp days they just scurry about, but on warm sunny days they often sit still and literally foam at the mouth. The bubbles they produce keep their gills moist so they can still breathe even while emersed. This biggish shore crab was working up quite a froth.
Nuttallina californica is one of the most common chitons seen around here. They often hunker down into small crevices where water will collect even at low tide. This individual was nestled among a clump of Phragmatopoma tubes; being closely surrounded by other animals will help keep its own body moist.
Unlike the hard granite that you’d find at the southern end of Monterey Bay, the rock at Natural Bridges is a soft, easily eroded mudstone. You can scratch it with your fingernail. Limpets take advantage of this soft rock by digging themselves little home scars, which conform perfectly to the contours of their shells and make a snug, water-tight fit. The limpet leaves its home scar to forage when the tide is in and returns to it as the tide recedes. The owner/occupant of this scar has likely died, as it wouldn’t have abandoned its home scar when we were there at low tide.
And speaking of limpets, Daniel and I spent a lot of time observing the owl limpet, Lottia gigantea. This limpet is noteworthy not only for its large size, but for its territorial behaviors. They are indeed large–the biggest ones I’ve ever seen are about the size of the palm of my hand–and the big ones are all females. Lottia gigantea is a protandrous hermaphrodite: individuals begin sexual maturity first as males, and then the lucky few turn into females.
The truly remarkable thing about L. gigantea is its ability to modify the environment. The large females maintain an area called a farm, from which they diligently remove interlopers. They will scrape off settling larvae of barnacles and mussels, and will push off other limpets. Lottia farms are very common at Natural Bridges; if you are here and see a suspiciously empty patch of rock amid the mussel bed, look for a big limpet hanging out on the edge of the empty spot.
The owl limpet has a good reason for keeping other animals off her territory. It provides her food. This animal is indeed a farmer. See the pale zig-zag markings in the Lottia farm? Those are marks made by the limpet’s radula as she grazes over the rock. All limpets are grazers, but L. gigantea actively manages her farm so that she feeds on one area while allowing the algal film to grow on other areas, then rotates to a new feeding spot as the old one becomes depleted. Pretty clever for a snail, isn’t it?
It felt really good to spend some quality time with Mother Nature again. I’m still taking it very easy, careful not to get overtired and to continue letting my brain heal. Getting outside for even short periods definitely seems to help.
Today’s online version of the San Francisco Chronicle published another follow-up article about last week’s rampage of bees in Concord, CA. The gist is that seven bees sent to the state Department of Food and Agriculture for testing, and the results showed that they did not possess Africanized alleles. This finding has led some to conclude that the bees that did the attacking were ordinary European honey bees. This, in turn, is a dangerous conclusion because the logical continuation of the thought process is that any hive of ordinary European honey bees kept in managed hives could suddenly and without warning become super aggressive. Let me address the study results as reported in the Chronicle, and then we can talk about the repercussions to beekeepers in California.
Thought #1: First of all, only seven bees were examined for Africanization. Seven out of several tens of thousands of bees in the colony. So yeah, sampling error is a problem.
Thought #2: Worker honey bees, all of which are female, are diploid. They inherit nuclear chromosomes from both parents. This is the same as happens for other diploid animals such as humans and most likely every other animal you would think of. The workers’ brothers, the drones, are haploid; they develop from unfertilized eggs and thus carry nuclear DNA only from their mother, the queen.
Thought #3: The test used by the state looked for the presence of Africanized alleles in the mitochondrial DNA (mtDNA) of the seven bees that were examined. In sexually reproducing animals, the female gamete (egg) is much larger than the male gamete (sperm). The sperm provides DNA to the zygote that results from fertilization, but little else. All of the other cellular components, including mitochondria, come from the egg. Mitochondria are nifty little bean-shaped organelles, evolutionarily derived from some sort of aerobic bacterium-type critter, that are the “powerhouses” of cells. They are the site of cellular respiration, where glucose molecules are broken down and the energy within the chemical bonds is released to fuel the cell’s activities. Mitochondria, as descendants of formerly free-living bacteria, possess their own DNA and are self-replicating units within eukaryotic cells. Because a diploid organism inherits mitochondria only from its mother, mtDNA can be used to trace maternal lineages through time.
Thought #3.5: A hive of European honey bees contains a European queen and her progeny. Her daughters, the workers, obtained half of their DNA from her and half from their fathers. A virgin queen mates with 12-15 drones on her mating flight before returning to her hive to begin laying. If some of the drones she mates with have Africanized alleles, then some proportion of her daughters will as well.
Thought #4: The results of the test used by the state cannot be correctly interpreted as indicating that there were no Africanized bees in the aggressive hive in Concord. Period. If the state wants to test for Africanized alleles, looking only in the mtDNA isn’t going to do the trick. They can examine every single damn bee in the hive, and all they will find is the same mtDNA that the European queen has. They are looking in the wrong damn place–they need to examine the nuclear DNA for Africanized alleles. Now, there could always be something unusual about the mitochondrial genome of honey bees that I’m not aware of, which would mess up my entire argument. However, I am not the only person who thinks that relying on mtDNA to determine Africanization tells the whole story. Eric Mussen, apiculturist emeritus at the UC Davis Department of Entomology and Nematology, said more or less the same thing a week ago, right after the attack happened.
Repercussions for beekeepers: Well, any beekeeper knows that public hysteria about bees is a real thing. Many people are frightened of honey bees and don’t want them around. Responsible beekeepers take measures to ensure that their bees are not a nuisance or danger to the public. We really want to do the right thing for our neighbors as well as for our bees. Shoddy science reported as fact doesn’t help our cause.
Saturday, 21 May 2016 — We had spent two hours tootling around the bay on Murray’s boat and had a late (and for me, second) breakfast at Aldo’s at about 11:00. We came out of the upper harbor and turned right onto 7th Avenue. Murray was driving his car, I was in the front passenger seat, and Alex was in the back seat behind me.
We crossed Brommer Street and continued south on 7th Avenue, going maybe 25 mph. I saw a white blur out of the corner of my left eye, a split-second before a car swerved out of the opposing lane and plowed into the front left corner of Murray’s car. I heard two distinct bangs: one was the impact itself, which you’ve heard if you’ve ever been in or witnessed a fender-bender, and the other was the explosion of the air bags. There was no squeal of brakes and there were no skid marks on either side of the street. Air bags deployed, car got pushed into the curb. Car filled with smoke and dust. A few seconds after the air bags deployed there was a third crash into the windshield directly in front of me. I couldn’t see what caused it because of the air bags and smoke, and thought the car was going to blow up with us inside it. The sense of disorientation after a car accident is pretty fierce. What with the loud noises, a car full of smoke and propellant, and air bags blocking the view out, it is really hard to understand what happened.
Fortunately there were several witnesses and passersby who helped us out. The guy in the car behind us was an off-duty out-of-town cop visiting for the weekend with his wife and kids. The passersby got us out of the car and called 911. The guy who hit us was sitting on the sidewalk and the off-duty cop asked him questions. From what I overheard the guy said he was on medication for schizophrenia and thought he was going to the beach; after the collision he had gotten out of the car and run over Murray’s car, stumbling or falling onto the windshield which explained how the windshield had gotten broken. He didn’t get far before collapsing on the sidewalk, I think. I could see that he was bleeding.
We were in Murray’s car, the orange Honda Fit on the left. See the inflated air bags and smashed windshield? The white powder is absorbent material that one of the fire fighters poured on the street to soak up all the fluids (mostly radiator fluid, I think) leaking out of the busted cars.
Emergency vehicles–2 fire trucks, 2 ambulances, 2 CHP officers on motorcycles–arrived on the scene after about 10 minutes and had the street blocked almost immediately. EMTs decided that the other guy needed help most; the lead EMT told one of the ambulance drivers that he would be a flyer (which we later learned meant he needed to be airlifted to a trauma center). The three of us were checked out by the EMTs (my blood pressure was 180/110, when it normally is in the 110/60 range–amazing what adrenaline will do) on the street and we decided to go to the ER on our own. The CHP officers asked us what happened and took our statements. One of them gave Murray a case number so he can follow up with his insurance company. Rogan came to pick us up. There wasn’t enough room in his car for all of us plus the stuff from Murray’s car so he and Alex took the stuff to Murray’s house while Murray and I waited for the tow trucks. Tow trucks arrived, smashed cars were hauled away, and Rogan came back to take us all to the ER.
Murray’s car being loaded onto the tow truck. Nice view of the side-curtain air bags.
What I don’t have a picture of is the passenger side of the car. The rear right wheel, which took the brunt of the force from colliding with the curb, was partially folded underneath the car.
Bottom line: We’re all okay, just bruised and battered. Alex and Murray both have nasty contusions from their seat belts. I have a stiff neck, muscle soreness around my ribs, a small abrasion/bruise on my right cheek, a bruised left knee, minor abrasions on my hip bones from the lap belt, and bruises on my right leg from knee to ankle (I think from hitting the dashboard?). The top of my head is starting to feel a bit abraded, nothing serious. We’ve been told to take it easy and that tomorrow we’ll feel worse than we do today. Ibuprofen + ice is the formula for the next several days. No strenuous exercise, either.
All the safety equipment in Murray’s car worked exactly as it was supposed to. Air bags kept us from being much more severely injured, and given that the other guy smashed into the windshield exactly where my head would have been, I’m feeling very grateful.
I was able to drive home, but confess to being leery driving on Mission Street. Passing within a few feet of cars going the opposite direction gave me the heebie-jeebies.
So, no working the tides this weekend for me. I’m glad it’s not one of the spring’s better low tide series.
Five days ago the residents of a suburban neighborhood in Concord, CA, got to experience first-hand what happens when a colony of Africanized honey bees takes over a hive of European bees. According to the most recent article in the San Francisco Chronicle, the original colony had been managed by a beekeeper for 15 years without any problems. Beekeepers conclude that the Africanized bees invaded the colony, killed the European queen, and took up residence. They became agitated when the beekeeper tried to move the hive last Friday. Several people were stung multiple times and two small dogs were killed.
The reason I bring this up is to calm fears. As I wrote last fall, we already know that Africanized honey bees have been in the greater San Francisco Bay Area since 2014. I’m willing to bet that there are Africanized alleles in the honey bee gene pool around Santa Cruz, too. Let me explain why I’m not overly concerned about Africanized honey bees.
As a beekeeper myself I am growing less and less tolerant of bees that are in the least bit jumpy or overly defensive; they make working a hive more stressful than it needs to be, which means the hive is open for a longer period of time, which means the bees get more anxious, which means the beekeepers get more anxious, and so on and so forth. Life as a beekeeper, especially in a suburban area, is much more pleasant when the bees themselves are gentle and sweet. In our experience, the Italian and Russian strains of the European honey bees have a docile temperament and are easy to work with.
There’s no doubt that the Africanized alleles are here, and they’re here to stay. I touched upon this the other day when I wrote about the bees in our pantry. I also have no doubt about the impact that hobbyist beekeepers will have to control the spread of those alleles for extreme defensive behavior. You see, by re-queening aggressive colonies whose queen may have mated with Africanized drones, a beekeeper removes those alleles from the hive, effectively diluting them in the larger gene pool. Hobbyist beekeepers would be selecting against defensiveness and for docility. Now, I am not a honey bee population geneticist, nor am I an expert on the different strains of European honey bees. However, I do know that if we consistently cull queens whose daughters are too jumpy or quick to defend their colony, then eventually we should end up with less defensive behavior as the Africanized alleles become rarer in the population.
I should also say that those Africanized alleles are not going away. We, beekeepers and non-beekeepers alike, have to accept that Africanized bees have been established in California for decades now and are expanding their range northward. A warming climate may enable them to overwinter successfully in areas that were formerly too cold for them. So we have them, and have probably had them for a while now. Most people encounter only foraging bees; these, whether or European or African descent, tend to be focused on their work and can’t be bothered to notice the big lumbering mammal watching them (unless said mammal does something to provoke the bees, in which case all bets are off). It is only when they detect a threat to their colony that the bees become aggressive.
So, what should you do? Well, if you see a feral colony of bees, don’t mess with it. This is the same advice that I’d give someone who asks how not to get bitten by a rattlesnake. Pay attention to your surroundings, even if you’re just walking the dog around the block. Who knows, a swarm of bees may have taken residence in a tree that you’ve walked past a thousand times before. If you notice bees flying into and out of a hole in a tree, watch them from a safe distance (binoculars are great tools for spying on bees). If you are concerned that a colony may be in a bad location because of proximity to people or livestock, contact a beekeeper who can remove it safely. Above all, keep in mind that in your daily life you do many risky things. If you don’t believe me, check out these data from the National Safety Council in 2002 for chance of death due to:
car accident as an occupant of a car: 1 in 17,000 (yikes!)
falling from stairs or steps: 1 in 180,000
suffocation in bed: 1 in 565,000
drowning in a swimming pool: 1 in 450,000
contact with hornets, wasps, and bees: 1 in 5,000,000
So don’t worry, but do be aware. And don’t let the threat of Africanized honey bees keep you from enjoying the outdoors! And don’t forget to look both ways before you cross the street, either.
