Warning: Brief appearance of adult spiders in this video.
Remember that egg sac I cracked open yesterday? Everyone was so concerned that the eggs would be vulnerable, so I checked up on them today.
They’re fine! So I show off some of my microscopy gadgets for a while.
The eggs have a hard, dry shell around them, and are nearly perfectly spherical. They roll around like teeny-tiny BBs in the petri dish.
I’m working on my spider-wrangling skills, so Mary and I were tinkering in the lab today, and I tried opening up one of the many egg sacs I’ve got now. Guess what it’s full of?
If you can’t trust the Sun/New York Post, who can you trust? This is their summary of a science article.
Drinking young people’s blood could help you live longer and prevent age-related diseases, a study has found.
Blood factors taken from younger animals have been found to improve the later-life health of older creatures.
The study, published in Nature, was conducted by researchers from University College London (UCL), who said it could reduce the chances of developing age-related disorders.
Gosh, that sounds like fun, so I clicked through to read the source.
I was so disappointed.
It’s a review article titled “Facing up to the global challenges of ageing”, and it’s not about wealthy vampires bleeding young people dry at all. It’s also not a “study”. It’s a summary of prior published research.
The main concern of the paper is a survey of all of the factors that contribute to late-life morbidity — if we extend lifespans, what’s the point if those last years are spent suffering with diseases of the aged? There’s a brief mention of “blood factors obtained from young individuals”, but that’s kind of it — the rest is detailed information about lots of identified problems. Here’s a taste:
Lifestyle interventions, while often beneficial, can be insufficient to prevent the progress of age-related problems, partly because of failures in compliance, and also because of limited and variable responses. Drugs are an additional option, and are already in widespread use for the prevention of cardiovascular disease, by pharmacologically decreasing hypertension and low-density lipoprotein cholesterol in healthy individuals who are at risk of cardiovascular disease (primary prevention). Treatment of the elderly is complex, since the relation between cardiovascular risk indicators, such as high body mass index, blood pressure and blood lipids, and end points, such as mortality, can change and even reverse with increasing age. The changing correlation with age could indicate that pharmacological interventions should depend on age and the presence of frailty and multimorbidity. However, mortality may be selective, with those sensitive to classical risk factors dying before the age of 70, or reverse causation may occur, with age-related diseases leading to low body mass index and blood pressure, and further work teasing out causality is needed. The ageing process in animals shows evolutionarily conserved, parallel and interacting mechanisms, known as hallmarks, that have proven to be modifiable, and several of these are also well-documented in humans. They eventually lead to unrepaired damage in DNA, accumulation of misfolded and aggregated proteins (for example, in the brain and the retina) and senescent cells (for example, in joints and kidneys) as well as to an inappropriate and persistent activation of stress responses, such as in the innate immune system (inflammaging). To develop further interventions to compress morbidity, including drugs, we need a better understanding of the roles of individual ageing mechanisms in different tissues and at different stages in life, and their contributions to the aetiology of age-related diseases. To this end, animal studies are useful to inform more targeted studies in humans.
It’s really hard to make a horror movie with good jump scares out of this kind of thing, but the NY Post tried. I’m sorry to say there was no mention of “drinking young people’s blood” anywhere in the paper.
Come on, Nature, this is probably why more people read the NY Post and the Sun than Nature. I also notice that Nature has a terrible lack of scantily clad girls on page 3.
Just watch the wheel of illogic turn in Jordan Peterson’s head.
lmao Jordan Peterson actually believes the Bible story about Adam and Eve, the snake and the apple confirms recent scientific hypotheses about how humans evolved to have eyesight. In other words, he believes the Ancients discovered DNA and postulated the theory of evolution 🤣 pic.twitter.com/bVvgBOl4wy
— ☀️👀 (@zei_nabq) September 10, 2018
First, we get a quick summary of the book of Genesis.
A snake gives them an apple, and that wakes them up.
Then he waddles off into a discursion about science. This is key, because he’s going to conclude by using science to validate his version of the Bible.
The reason that humans have such great vision, way better than most animals, except for raptors, is because our visual systems were designed to detect predatory snakes.
Friggin’ bollocks.
He cites a book by a primatologist whose name he can’t remember on this “fact”. The evidence is a lot weaker than he implies.
Snakes were “the first and most persistent predators” of early mammals, says Lynne Isbell, a behavioral ecologist the University of California, Davis. They were such a critical threat, she has long argued, that they shaped the emergence and evolution of primates. By selecting for traits that helped animals avoid them, snakes ultimately endowed us with forward-facing eyes, for example, and enlarged visual centers deep in our brains that are specialized for picking out specific features in the world around us, such as the general shape of a snake’s body camouflaged among leaves.
Isbell published her “Snake Detection Theory” in 2006. To support it, she showed that the rare primates that have not encountered venomous snakes in the course of their evolution, such as lemurs in Madagascar, have poorer vision than those that evolved alongside snakes.
There is no strong correlation. I read Isbell’s paper, and there is no statistical comparison, which would be difficult given the lack of specificity. Here’s the extent of the “species comparisons” she did.
Malagasy prosimians have never co-existed with venomous snakes, New World monkeys (platyrrhines) have had interrupted co-existence with venomous snakes, and Old World monkeys and apes (catarrhines) have had continuous co-existence with venomous snakes.
To which I have to ask, “Why restrict yourself to venomous snakes?” New World monkeys have as much to fear from constrictors as they would from venomous snakes. I think the answer might lie in her reasoning in response to the argument, “but then why haven’t rodents evolved bigger brains and sharper vision?” — it’s because she argues that rather than visual adaptations, rodents evolved to become more resistant to venoms. It’s an entirely adaptationist hypothesis, of course, which is OK…but when an adaptation is turned into an umbrella hypothesis which explains everything with a single cause, I get a little leery.
At least the paper has the best “What have the Romans ever done for us” line I’ve seen in a scientific work.
What besides visually guided insectivory, feeding on fruits and nectar, moving on fine terminal branches, or leaping could favor better depth perception in near space and a better ability to “break” camouflage, both of which are improved with orbital convergence, particularly in the lower visual field?
Her answer, obviously, is “snakes!”
Trust Peterson to ignore the multiple factors that contributed to our pattern of evolution to focus on just the one that he can twist to stand in defense of the fundamental truth of the Old Testament. If only the story had told about how Eve, a hairy, monkey-like creature, crept along the branch of a pear tree gathering ants for breakfast before leaping to the apple tree, finding both a snake and a ripe apple waiting for her…
Once again, though, Peterson is going to use a mention of snakes in the scientific literature to suggest that the authors of the book of Genesis had a startling and anachronistic understanding of evolutionary theory thousands of years before Darwin.
Our visual system, which is the ability to see, and to be enlightened let’s say because enlightenment, for example, is associated with vision, the snake gave that to us because we had to pay attention to predatory things that were after us for tens of millions of years.
Well then. Basically every animal has had to pay attention to predatory things. Do they all get enlightenment? It’s almost as if there has to be more to the explanation than just, “Yikes! A snake!” As if, maybe, the Genesis tale is more of a poetical metaphor than a scientific description of a phenomenon.
And fruit, that’s interesting, we have color vision because we are fruit eaters. Our color vision is precisely evolved to detect ripe fruit.
No it’s not. That’s part of the story.
We don’t have particularly good vision, or even particularly good color vision (the exceptional qualities we do have arise from more elaborate visual processing in our brains). Other vertebrates, like reptiles, fish, and birds have tetrachromatic vision — they have four opsins, or color filters, in their eyes. Mammals are descended from a common ancestor that lived in the Cretaceous and was nocturnal — it foraged in the dark at night, when the less sensitive color opsins were useless, and they lost all but two color opsins. We primates secondarily evolved a third opsin by gene duplication approximately 30-40 million years ago.
So I guess the book of Genesis is all about the catarrhine radiation sometime in the Eocene?
Also, the “ripe fruit” story isn’t as straightforward as he claims.
Another approach in trying to understand how primate colour vision evolved is to examine directly how behaving animals exploit colour information. For this purpose, the polymorphic platyrrhines have provided an invaluable resource, since we know that (i) opsin gene polymorphisms responsible for the colour vision variations in platyrrhine monkeys have been maintained by natural selection over long periods of time and (ii) individual monkeys in these species are forced to deploy strikingly different colour vision capacities to achieve common life-supporting goals. Studies of such species can ask, for instance, whether animals with alternative colour vision arrangements are better or worse at particular foraging tasks. In tests run under semi-natural conditions, trichromatic monkeys proved to be more efficient at gathering foods predicated on the use of colour cues than were dichromatic conspecifics. Although such outcomes imply that trichromacy could have evolved in the service of efficiency in food harvesting, other research suggests that the story may be more complicated than that. For instance, several sets of observations made on monkeys feeding in natural circumstances found no causal relationships between colour vision status and efficiency in foraging. Supporting this conclusion is a recent examination of the efficiency of fruit gathering in polymorphic spider monkeys (Ateles) that also detected no differences between dichromatic and trichromatic animals. This experiment focused specifically on foraging that is conducted over very short range (within an arms length) and the physical feature of the target fruits that best predicted foraging efficiency was not colour, but rather luminance contrast, a cue that should be equally available to trichromatic and dichromatic viewers. It may be noted that short-range foraging such as this also allows for the exploitation of various non-visual cues.
Researchers have had little difficulty in identifying potential advantages that might explain why colour vision evolved in the way that it has among the primates, but so far have had less success in demonstrating which among these may hold greater importance or, indeed, whether any single set of circumstances may provide a general explanation. Future studies on this topic will no doubt continue to exploit the exceptional opportunities for study offered by the polymorphic platyrrhine monkeys, while having to pay closer attention to the physical details of the viewing environment operative for a range of natural behaviours.
Always question those pat answers that ascribe a complex phenomena to a single cause. Our color vision is a contingent property of a fortuitous event in a successful distant ancestor; we’ve opportunistically used it in our species for many functions, whether it’s gauging the ripeness of fruit or getting more cues in foraging or detecting social cues or creating art or labeling our side with blue vs. red.
We didn’t get it from a snake peddling apples. But here’s where we see Peterson make the fallacious conclusion that yes, we did, and further, a group of priests in Palestine 2500 years ago had secret knowledge of the evolution of primates in the Paleogene, and wrote a metaphorical history of the catarrhines.
So that part of the story is right.
No, it’s not. The bullshit generator in Peterson’s brain has assembled a rationalization that falls apart when examined by anyone with basic knowledge of evolution.
I spent a good chunk of my morning fussing over my spider colony, tidying up their vials and making sure they all had food (crickets for the larger ones, wingless fruit flies for the little guys.) I currently have 10 total adults, 8 females and 2 males, and a countless swarm of spiderlings that I’m gradually sorting out into individual dishes.
The current roster:
Females:
The ones in blue have had a successful hatching, and are currently sharing their vial with some unknown number of babies. I’m slowly working on separating them.
The ones in red have an egg sac.
This is promising — they seem to be awesomely fecund. I’m going to have to wait on supplies before I can start doing mad science on the embryos, though. For now I’ll be content with just building up the colony and figuring out what I’m doing.
Uh, about Larry…Larry’s on the small side, and I initially only got a rough look at their morphology with a hand lens, and just today I got a good look under the scope. Larry’s a girl. Come on, people, I’m new at this — I’ll keep practicing at recognizing their sexes.
Males:
Fewer males. I don’t know whether it’s due to high mortality upon encountering females, or if it’s just sampling bias. They are smaller and harder to spot.
These are all wild caught adults, found in our garage and sun porch. Credit where credit is due: Mary found them all, and lately she’s been catching them herself. True story: I was just reading papers, and had put together a few vials and things to begin the process of spider catching, when she told me there was a lovely spider on the door of the sun room, and asked was it the right species? And of course it was, so I clumsily scooped up Amanda and took her to the lab. And now Mary has the search image for these spiders locked into her brain, and she prowls around and spots them with her eagle eyes, and I haven’t had to do a lick of work.
Bad news, everyone. Fred is dead. Betty ate him. I’m hoping he at least fulfilled his biological destiny before getting his guts sucked out.
More bad news: as I expected, baby spiders are murderous little cannibals, and there’s been a fair bit of fratricide going on, even though they had plenty of fruit flies strolling about. I’ve now separated them all and the survivors now have their own little chambers with their own little fruit fly to gnaw on.
I made a quick video update. Don’t watch it if you’ve got the arachnophobia.
Here’s a story about a lab that has a substantially greater investment in spider science than I do.
NOAA
I was a bit disappointed with this video.
Some might not know just how diverse teratology is… How might your scientific research fit in? We're guessing, pretty well. Find out why in this video. #IamTeratology #science #research #professionaldevelopment pic.twitter.com/hrXRsw11jy
— Teratology Society (@TeratologySoc) September 6, 2018
Some of us see teratology as a tool to probe normal developmental processes — it’s been that way for centuries. Teratology is the science that studies the causes, mechanisms, and patterns of abnormal development. It’s much more than just figuring how to prevent or correct human developmental disorders…not to belittle that extremely important aspect of the discipline.
If I were to write a diet book (not that I’m at all qualified to do so), it would be one page long and that’s what it would say, and it wouldn’t sell. What you need for a successful diet book is a gimmick, a distraction to keep your mind away from the awful, impossible mantra of “Eat less, exercise more”, because that’s what people will pay for. “Oh, I can eat all the bacon I want as long as I avoid asparagus? That’s the diet for me!”
Yvette d’Entremont takes on the keto diet, which is the latest incarnation of a long line of wish-fulfillment diet strategies. The Atkins diet, the Paleo diet, and now the Keto diet are all rationalizations for consuming all the high calorie, fat-rich foods we crave with the magic trick of shunning one other kind of food. The scientific studies show they don’t work, or at least don’t work the way their proponents think they do. The simple formula is still the hard truth.
You could pick any of the countless diet books on the market, follow their plan to the last calorie, and lose weight. This is because — as study after study has shown — calories and dietary adherence matter more than anything for weight loss. You can gain or lose weight on any combination of foods. People have lost weight on twinkies, McDonalds, juice, plants, and obscene amounts of meat.
It’s important to remember weight loss alone doesn’t necessarily cause all health markers to improve, and a diet causing weight loss does not mean it’s appropriate and healthy for everyone. Some foods are better than others at making weight loss and maintenance easier for different people, so balancing a diet is a fairly personalized thing. If your doctor gives you the green light and keto works for you, do it. If low fat works for you, do it. If plant-based, paleo, Mediterranean, or one of the zillion other diets help you improve your health and your relationship with food? Do it. There’s no one right way to eat for everyone, just as there is no miracle diet plan for weight loss.
Also — here’s an article by a woman who got to experience a metabolism chamber and actually measure directly how food intake affected her caloric output. It’s got lots of solid, basic information on human physiology, and concludes much the same thing.
When it comes to diets, the researchers have also debunked the notion that bodies burn more body fat while on a high-fat and low-carb ketogenic diet, compared to a higher-carb diet, despite all the hype.
“We could have found out that if we cut carbs, we’d lose way more fat because energy expenditure would go up and fat oxidation would go up,” said Kevin Hall, an obesity researcher at NIH and an author on many of these studies. “But the body is really good at adapting to the fuels coming in.” Another related takeaway: There appears to be no silver bullet diet for fat loss, at least not yet.
That “not yet” is optimistic. I think we’re just going to have to face the fact that our cellular metabolism has been optimized by billions of years of evolution to be flexible and responsive to the environment…as if that isn’t a good thing.
Uh-oh. I just submitted my first grant application (a small, in-house grant to do pilot studies) for spider research. This might be getting serious.
In more routine news, I added a new fellow to my stable today: Larry. He’s now savoring a meal before I throw him to the loving mercies of the lady spiders.
In case you were curious about how to identify spider sex, I’ll explain below the fold.
