That’s the Pinwheel of Doom

Oh, what a pretty pinwheel! Until you look at what it illustrates. The height of each bar is the approximate number of hazards to the human concern listed from the impact of climate change. We’re in big trouble because each hazard compounds the others — it’s saying that if one thing doesn’t get you, something else will, and here’s an objective attempt at real risk assessment.

Six different aspects of human systems are shown (health, food, water, infrastructure, economy and security), with their subcategories for which impacts were observed. The heights of the bars indicate the number of hazards implicated in the impacts. Here we analysed ten climate hazards. The complete table of climate hazards and human aspects impacted is available at http://impactsofclimatechange.info.

The authors conclusion could be shorter. They could have just written “We’re fucked.”

Given the vast number of components in coupled human–climate systems, assessing the impacts of climate change on humanity requires analyses that integrate diverse types of information. Contrasting temporal and spatial patterns of climate hazards, compounded with varying vulnerabilities of human systems, suggests that narrow analyses may not completely reflect the impacts of climate change on humanity. Our integrative analysis finds that even under strong mitigation scenarios, there will still be significant human exposure to climate change, particularly in tropical coastal areas; such exposure will be much greater if GHG concentrations continue to rise throughout the twenty-first century and will not differentiate between poor or rich countries. The multitude of climate hazards that could simultaneously impact any given society highlights the diversity of adaptations that will probably be needed and the considerable economic and welfare burden that will be imposed by projected climate change triggered by ongoing GHG emissions. Overall, our analysis shows that ongoing climate change will pose a heightened threat to humanity that will be greatly aggravated if substantial and timely reductions of GHG emissions are not achieved.

Every election from here on out is going to be all about who is going to save my grandchildren from onrushing doom.

Camilo Mora, Daniele Spirandelli, Erik C. Franklin, John Lynham, Michael B. Kantar, Wendy Miles, Charlotte Z. Smith, Kelle Freel, Jade Moy, Leo V. Louis, Evan W. Barba, Keith Bettinger, Abby G. Frazier, John F. Colburn IX, Naota Hanasaki, Ed Hawkins, Yukiko Hirabayashi, Wolfgang Knorr, Christopher M. Little, Kerry Emanuel, Justin Sheffield, Jonathan A. Patz & Cynthia L. Hunter (2018) Broad threat to humanity from cumulative climate hazards intensified by greenhouse gas emissions. Nature Climate Change doi.org/10.1038/s41558-018-0315-6.

Crickets are bad, mmm-kay?

Disaster struck this weekend. I gave my fully-grown, big ol’ adult spiders crickets to eat. Now Vera is a monster: she just ropes ’em up, immobilizes them fully, and then bites them. So I was overconfident and gave crickets of the same size to Amanda and Xena.

The next day, Vera is a huge bloated sack of bug juice and her cricket is in fragments. Amanda and Xena are gone, and their crickets are sitting there smug and happy. Turns out crickets defend themselves by kicking predators, and poor Amanda and Xena were beaten to death and then eaten by the evil Gryllidae. This does not make me happy. I’ve got to find a safer food source. For now, I’m just giving the juveniles and the sole survivor lots of fruit flies. Death to all crickets!

In other spider news, I’ve been frustrated by the fact that none of them are producing eggs right now, and all the wild specimens have vanished from their usual haunts as winter descends upon us. Then, last night, I woke up in the wee hours with a sudden obvious thought.

Remember that movie, Silent Running?

There’s this scene where the space-going ecologist is concerned about how all the trees are losing their leaves, which are turning brown and falling off, and he hits the books trying to figure out what disease is killing his forests. And then he suddenly realizes, oh, autumn, seasons changing, all that, and I’m sitting in the audience thinking, you dope, of course, so he runs around setting up lights to create a growing season in the space domes. Yeah, I’m also a dope who didn’t think of that, and I should have, because I’ve got timers and lights for my fish rigged to put them on a 14/10 light/dark cycle. This is routine lab animal maintenance. D’oh!

So now I’m going into the lab this morning to put up lights and trick the spider colony into thinking it’s Spring, and time for love, by wiring up the incubator.

Friday Cephalopod: Why are some cephalopods so clever?

I’m just ruined for some things. Here’s this article that’s smack dab in my wheelhouse: Grow Smart and Die Young: Why Did Cephalopods Evolve Intelligence? It’s a topic I’m very interested in, but the article fell flat for me. I’m going to be a bit nit-picky here.

The good part of the story is that it’s a review of various hypotheses for the evolution of intelligence in various clades. They propose 3 general classes of hypotheses.

  1. The Ecological Intelligence hypothesis. Intelligence arose in response to food foraging challenges. You’ve got to have a detailed knowledge of your environment in order to take advantage of scarce or difficult to extract food sources.
  2. The Social Intelligence hypothesis. Animals with complex social interactions build complex brains to match.
  3. The Predator/Prey hypothesis. Avoiding predation in some organisms might require an intelligence comparable to that required to negotiate social interactions.

Not mentioned is an alternative sort-of null hypothesis: there was no selection for intelligence at all. It hitch-hiked along with an expansion of neural tissue associated with morphological changes — intelligence is something that just emerges with a surplus of brains that arose for other reasons.

OK. With my addition, I think this is a reasonable framework for discussing the evolution of intelligence. Unfortunately, the paper has a couple of problems. One is that, well, it’s a review paper that doesn’t have any data or experiments or even any real evidence. It’s speculative, which is fine, but I went into it with higher expectations.

The one piece of information I found useful, though, was this table, which gathers together information about groups of animals with a reputation for intelligence and puts them in a comparative context. That’s what I like to see!

But. Here’s what bugs me: it’s comparing a whole taxonomic class, the cephalopods, with a couple of families. The cephalopods are diverse, with some impressively intelligent representatives, like the octopus. But market squid? Are they particularly bright? I don’t think so. We could say the same of primates — are we really going to compare Galago with Homo? This table would have benefited from a much tighter focus.

It also leaves out some features unique to various groups. Can we compare complex active camouflage with complex language? It seems to me that maybe there are different preconditions that can lead to intelligence, and maybe an illustration of the significant differences between them would be more informative? There could be many, radically different paths that lead to increased demands for more flexibility and intelligence — maybe all three of their hypotheses, and more, are all true.

For instance, look at the last rows of the table, on life history. That part is really interesting, and the paper does discuss it at length. Some cephalopods are intelligent creatures that are cruelly cursed by their nature with very short lifespans of 1 or 2 years, where reproduction is often a death sentence, and the opportunity to educate offspring is non-existent. What intelligence they do have has to be inherent, because there is so little opportunity for learning.

Also compare social lives. Cephalopods, depending on the species, are either solitary or live in large schools, and do not seem to form long-term social bonds; the vertebrates on the list are all social to various degrees, and do pair-bond. After reading the paper, I came away thinking that I mainly saw diversity and different forces that could all lead to intelligence, and don’t have much unity of mechanisms. There is at least a nice summary of cephalopod evolution.

Around 530 Mya a group of snail-like molluscs experienced a major shift in their morphology and physiology: their protective shell became a buoyancy device. The comparison with nautiluses, the only extant cephalopods that retained the external shell, suggests that this key event co-occurred with the emergence of arms, funnel, and crucially, a centralized brain. The increase in computational power at this stage might have been selected to support arm coordination for locomotion and object manipulation, as well as navigation in the water column and basic learning processes. Next, around 275 Mya the external shell was internalised (in the ancestors of cuttlefish and squid) or lost (in those of octopuses). It has been speculated that competition with marine vertebrates was a driving factor that led to dramatic changes in the lifestyles of these animals. First, the disappearance of the external shell allowed animals to occupy a wide array of ecological niches. Consequently, modern cephalopods are found in all marine habitats, from tropical to polar waters, and from benthic to pelagic niches. Second, the loss of the protective shell drastically increased predatory pressures and consequently the rates of extrinsic mortality. These novel ecological conditions might not have only played a major role in the emergence of sophisticated biological adaptations (e.g., lens eye, and chromatophores) but also in the coevolution of intelligence and fast life history of cephalopods.

Maybe intelligence is something that just arises in response to complex life strategies, where “complex” is an all-purpose buzzword for any of a million situations. If we ever meet aliens on a distant planet, this tells me you’d be unwise to try and predict what they’d look like or how they live or what the mechanisms behind their intelligence might be.

Vera is a beast

Today was cricket-feeding day. I am still learning things, and one of the things I have learned is that I hate crickets, those jumpy, twitchy, annoying little beasts. I have to struggle to confine and catch the things, but I chortle evilly when I finally slide them down into a vial. They’re two or 3 times larger than my spiders, but it’s no contest. They’re doooooomed. Bwahahahaha!

Also, spiders have personalities. Amanda is shy; she gets a cricket, she ignores it, and me, and just hangs out in her corner placidly until I leave the room.The cricket will be dismantled fragments the next day, but a lady does not make a spectacle of her murders.

Xena is timid. She notices the cricket for sure, but she runs away — where it is, she is not, and she scurries about rather frantically to avoid it. She lays down lots of webbing, though, and I think she waits until it snares itself thoroughly before going in for the kill.

Vera is a beast. Put anything in there, she does not delay sinking her fangs into it. I’d just put the cricket in her vial when she charged up, lassoed its hind limbs, and was making quick bites into the leg joints. She reminds me of Gwyneth, a real killer. Especially that bit about first knee-capping her prey before getting into the serious business of liquefying its guts.

Vera also escaped, briefly, and marched up onto my hand and stood there, gently tapping on my knuckle like she was getting impatient. Once the cricket was in her vial, though, she quickly rappelled down and made short work of it.

I’ve got to get them some mates, but I’m worried that the juvenile males are just too small — I may try tomorrow, though, when the females are fat and sated with cricket juice and might be willing to tolerate a conjugal visit. I’ve got a son of Gwyneth I’d like to pair up with Vera — what beautifully voracious slayers their progeny might make!

(I might be getting a little too close with my arachnid brood, I willingly confess.)

Spider poop

As promised threatened, I took some photos of spider poop this morning. It’s surprisingly colorful! But then, these are from the spiderling vials, so maybe it’s like baby poop, which also tends to have surprising colors.

The big circular feature is an artifact at the bottom of the plastic vial.

This is my masterpiece: I call it “Still life with spider poop, molted cuticle, and little blue bits of dried fly medium”. I’m thinking of printing it out on a 10 foot wide sheet and selling it to MOMA.

Spider Update: Cleaning day (no photos)

I’ve concluded that I’ve been a terrible spider daddy. What else can you say when your young spiderlings have a 90% mortality rate? I expect ICE to pound on my door any day now and give me an offer of employment at one of their detention centers.

In my defense, I am learning. My big mistake was hoping that I could keep a freshly-hatched clutch of spiderlings together for a fairly long period of time, to minimize the maintenance chores. Nope. Doesn’t work. I even did some quick experiments where I’d put small groups of 3 in vials of different volumes, so different population densities, and it didn’t help. After a while, there would be only one.

I don’t know whether it was simply that one would hog all the food, starving the others, or whether it was outright siblicide, but lesson learned: the babies get separated, day one. I just have to get a new egg sac first. Unfortunately, all I’ve got now are 3 full grown adults, and they’re all females (it’s their own damn fault, too, since they ate their husbands).

Today was cleaning day and sorting out all the juveniles. At this point, I have a grand total of…11 young’uns. They all look healthy and I don’t expect serious mortality issues from this point on. About a quarter of them are male (you will say, “what’s 25% of 11?”, and I will reply that one of them is ambiguously sexed at this point, with palps that aren’t quite fully developed), but I can’t use them to breed with the adult females, yet. It’s not a worry about incest, but just that they’re roughly 1/4 to 1/2 the size of the adult behemoths, and they’re too preciously few to risk turning them into snacks.

Speaking of incest, 82% of the juveniles are children of the dearly departed Gwyneth, so there goes genetic diversity already. That may not be a bad thing, given that Gwyneth was an uber-fertile monster queen, and a little inbreeding to reduce genetic diversity is useful in a lab model. I’m also planning to do some collecting trips this Spring, to get individuals who didn’t all come from one house on one corner of one block in Morris, Minnesota.

Anyway, right now they’re all tucked into fresh new clean vials, given a little spritz of water vapor, and a couple of hapless fruit flies each. They just need to grow now. Also, I have a sink full of dirty vials to wash out tomorrow. Spider poop, yuck.

Hey, maybe tomorrow I should take some pictures of spider poop — I suspect most of you haven’t seen it.

A quick spider update (no photos)

The last time I mentioned my spider work, I had sad news: the eggs were dreadfully dessicated, and I hypothesized that the declining humidity was not good for their health. I have no new egg sacs, but I did increase the humidity in the incubator, and have other good signs to report. There has been zero mortality among the juveniles this week, and the adults were extraordinarily lively — so lively that I had to deal with 3 escapes while I was trying to feed them.

I had spiders crawling all over me, which was a delightful feeling, but also made me a little panicky — I had to get them back into their nice safe vials before they got injured. All were rescued, no harm done, and they also immediately chowed down on the juicy flies I’d given them.

I felt all paternal and warm inside, as one does when dealing with affectionate pets.

Good news, bad news

All my life, I’ve had this dichotomy staring me in the face: my mother’s side of the family tends to live to a ripe old age, I knew my maternal great-grandparents, my grandmother lived on to old age despite a rough life, and my mother is still around (she may outlive me). On my father’s side, though, it’s like the grim reaper marks everyone for death as soon as they hit their fifties. My paternal grandfather died when my dad was a kid, my paternal grandmother died when I was 12, and my father died when he was younger than I am now. So I’ve always wondered which side of the family I was going to take after.

It turns out it doesn’t matter! There’s a new analysis of the genetics of human longevity with a gigantic data set.

Starting from 54 million subscriber-generated public family trees representing six billion ancestors, Ancestry removed redundant entries and those from people who were still living, stitching the remaining pedigrees together. Before sharing the data with the Calico research team, Ancestry stripped away all identifiable information from the pedigrees, leaving only the year of birth, year of death, place of birth (to the resolution of state within the US and country outside the US), and familial connections that make up the tree structure itself.

The SAP included almost 500 million individuals (with a single pedigree accounting for over 400 million people), largely Americans of European descent, each connected to another by either a parent-child or a spouse-spouse relationship. The scale of the data allowed the researchers to get accurate heritability estimates across different contexts; they could stratify the data by birth cohort or by sex or by other variables without losing the power needed for their analyses. They employed structural equation modeling—a technique that hasn’t often been applied to this problem due to the amount of data required for it to be productive—to calculate life span correlations and heritability across the giant pedigree.

Yadda yadda yadda. OK. I’m impressed with the methods. Now I want the answer: tell me my fortune, how long will I live? And the answer is…

By correcting for these effects of assortative mating, the new analysis found life span heritability is likely no more than seven percent, perhaps even lower.

The upshot? How long you live has less to do with your genes than you might think.

You can’t really tell from the genes. Environment and experience matter more.

This is good news: my paternal genetics aren’t a death sentence. But it’s also bad news: my maternal genetics don’t mean I can coast into my 90s. I have to try and replicate the life history of my maternal relatives.

Let’s see…

  • Live in a cold northern climate, like Minnesota. Check.
  • Eat more lutefisk.
    Uh, we might have a problem here.

Note: This result does not mean that genetics doesn’t matter. It means longevity is a complex, multifactorial trait, that many genes work in concert to allow for a long life, and that we inherit a mix of genes, some deleterious, some beneficial, such that you can’t easily estimate the role of the combinations you get from looking at your relatives. Also, as we all know, there is a huge environmental component: I could have the best suite of longevity genes, but if I start smoking cigars and drinking a quart of whisky every day while practicing a high wire act without a net, I may not last for long. There’s also a component of just simple chance.

So forget about genetic determinism. Just live the best life you can.