The universe, our lives, all this stuff – it’s just so incredible it sometimes boggles my mind how we can just walk around, doing whatever it is that we’re doing, just taking all this stuff for granted, overlooking everything. There’s so much to see, to appreciate!
I’ll start here – with a picture of a rock:
It’s not just any rock though – it’s been through a lot. Almost too much to imagine. Allow me to demonstrate what I mean by that…
Now, I should note that I think that timescales are funny things. I sometimes sort of feel like I don’t really understand them, how they work. I have similar problems with distances now and then, but we’ll get to that later. Of course it’s not that hard to imagine an hour passing by, or a day, or perhaps even a year. But a millenium? I don’t really have a good idea how much time a millenium is – it’s such a long time it boggles the mind. A million years? That’s just crazy. I have no way to conceptualize that kind of time-scale, my mind is much too small for that. So recently I tried to come up with a way to imagine how much time these big multiples of the numbers we usually use to denote time passing by actually represent. I decided to engage in a thought experiment where I’d be counting the years that have gone by and see where I’d end up, starting out where we are now. I pretend I’m able to count one year each second. That way 60 years will go by in just a minute – an entire life of a human being in just a minute. After an hour of counting I’d be close to the starting point of written history; we’d now be 3600 years into the past. We all sort of tell ourselves that we know roughly how long that is; the Jesus stuff is supposed to have happened 2000 years ago, and 3600 years isn’t that different from 2000 after all. But here’s a picture:
This is the Sicilian Temple of Juno Lacinia, and this is what 2400 years – just 2 thirds of the amount of time we’ve counted so far – looks like from a certain point of view.
Let’s count on: After a day of counting we’d be 86.000 years into the past – so what happened 86.000 years ago? We have little idea, it’s so very long ago. After a year of counting without rest, we’d be 31 million and 536 thousand years into the past – you can count one year each second every second without pause for an entire year of your life and you’re not even half-way to the dinosaurs!
If we assume you count every second of your entire life and you can expect to live 75 years, then the last number you’ll get to is the year that happened 2 billion 365 million and 200 thousand years ago.
Here’s the kicker: The rock in the image above is much, much older than that.
I’ve been to Copenhagen a few times this year. My parents also went there not too long ago – they came to the city and went back home the same day, for reasons which are not important here. I’ll pretend the trip was 220 kilometres each way; it’s close enough.
200 km is actually a really big distance, once you start thinking about it. We usually don’t, because we have means of transportation that will bring us very fast from A to B. So I decided to think about what would happen if we didn’t have those things; what if they had had to walk to Copenhagen instead of going by car? Well, walking takes more time, but it’s also a lot harder. So I decided to say that it probably wasn’t realistic that they walked more than 12 hours per day, at 5 km/hour. Or 5000 meter per 60 minutes, if you’re of a different persuasion. How long would it have taken them to get back and forth? Well, 5 km/hour and 12 hours per day gives 60 km per day, or 420 km per week. 220 km each way adds up to 440 km in total. So they’d have had to walk for more than a week to get to Copenhagen and back. It would have taken them more than a month to walk to Paris (~900 km) and back.
The closest big thingy you can see at night when you look up into the sky is basically a big rock which reflects the light of a huge ball of fire which luckily is quite a bit farther away from us than the big rock is; a ball of fire which has been burning without stop for a much longer amount of time than you can count years during your life. We like to think the big light-reflecting rock up there is quite near us; some humans have even been up there, so it can’t be that far away, right? Actually it isn’t – from a certain point of view. It’s average distance to Earth is around 385.000 km. If you could ‘fly-walk’ at a very human speed of 5 km/hour, you’d be there in just 17,5 years or so. You could leave at the age of 15 and be back here again at the age of 50. If these kinds of things were possible, which of course they’re not.
Here’s a different way to conceptualize that distance: Let’s think in terms of human-scale magnitudes (one human = ~1,5-2 metres), so that the distance is now 385.000.000 metres, instead of all that cheating with metrics like kilometres. Let’s say an average human is close to 2 metres tall and let’s say we wanted to get up to the moon by standing on top of each other; in order to reach them moon, you’d need something like 200 million people. Let’s do the counting thing again: Count one person per second. It’d take you close to 7 years to count the people you’d need to make that happen. (Of course there are various reasons why that kind of thing wouldn’t work.)
I mentioned that ‘the average distance’ was 385.000. It’s an average because the Moon is moving very fast, just like the Earth, and it doesn’t move around in a perfectly spherical manner. But the Earth and Moon is – as people know these days, although it took a very long time to convince all those well-dressed monkeys that that was how it worked – moving around the Sun as well, and this is where it gets a bit more interesting. The movement around the Sun is, well, fast. The Sun is approximately (such a wonderful word, considering which kinds of distances and differences are actually hidden here) 150 million km away from us. We don’t have enough humans to do the same trick we did with the Moon, not even close. But let’s look a little closer at the speeds involved. The average distance to the Sun is of course not the distance that the Earth travels during a year – the latter number is quite a bit larger, and like many other things it involves the number pi. The Earth goes roughly one billion km/year (940 million km/year, assuming the orbit is circular), which is 108.000 km/hour! Or 30 km each second. It’s almost unbelievable that we don’t notice, that we don’t fall off – that everything just happen the way things do, without anyone sparing much thought as to how utterly insane this is. We don’t even notice.
There’s a lot more on stuff like distances and time frames at Khan Academy.
Now, a different thing you could wonder about is how you can even think the thoughts you’re thinking now. It’s incredibly hard to understand what’s going on there, and we don’t have a very detailed model of the brain as it is. So let’s be less ambitious – let’s just have a look at some of the cells you have hanging around in ‘your body’. Here are a few juxtaglomerular cells, the likes of which are now hanging out in your kidneys (doing useful stuff):
There are a lot of different types of cells in the human body, and the total number of cells in your body is much higher than the number of humans on Earth. So you probably shouldn’t try to count them, like we tried counting other stuff before – you won’t get very far. Obviously they’re probably not very big, given that we don’t seem to notice them in our day-to-day lives even though there are so many of them. Until a few hundred years ago we didn’t even know such things existed. Now we do, and each day we as a species learn more about the almost infinite number of awesome small living things hanging around everywhere here on Earth. There are so incredibly many of them that cooperate with each other to keep you alive, and even though some of the types of cells in your body live only for a few hours, the combined work of all of them keep ‘you’ going for years, decades. So many things could in theory go wrong – after all even a single cell messing up and dividing the wrong way can end up killing you. Yet somehow things very rarely go wrong, you stay alive, year after year, until one day the little ones have done all they can for ‘you’ and so start worrying more about themselves than about what made you you.
These small things have been around about as long as the rock in the picture above has.
On top of all that… If you look even closer at the cells we talked about, you’ll see that they’re made up of tiny little atoms which are jiggling around all the time, everywhere, at insane speeds and in complex patterns we don’t always understand very well at all. Even though cells are really small, it takes a lot of atoms to make a cell – a lot of atoms which need to constantly ‘cooperate with-’ and interact with each other to maintain the structure of the cell. We talked about how there were more cells in your body than there are humans on Earth; it turns out that the number of atoms in a cell is roughly the same as the number of cells in a human body - 1014, or 100 trillion. The little atoms get broken down and reassembled in all kinds of ways, all over the place, all the time. I sometimes find it very confusing how all these interactions, all these things can happen everywhere and all the time, right under our noses (and over it, and in it, and…) without us being any the wiser. We look at the world and our eyes interpret the light which is available to us in a manner which the organisms which came before us benefited from. The way our eyes work is part of why we’re alive, why we’re here today – they enabled our ancestors to spot other huge collections of atoms and cells in order to facilitate the most optimal types of interaction with all those other collections of cells and atoms. Oh yes, our eyes are immensely useful things, and if you go into a bit more detail about how they work they’re fascinating things in and of themselves – yes, but even so: Such a profoundly limited, such a coarse-grained view of the world they have given us, compared to what actually is going on!
Or you could talk about the waves, all the different kinds of waves moving around in our environment – sound, heat, light, … Many of them humans can’t even see or feel, and many humans have lived their entire lives without ever knowing they even existed. Just as many people don’t know what that rock at the beginning really looks like when you start to zoom in, and which factors have caused it to look the way it does now, so relatively unharmed by time. I’ve read some stuff about rocks, but I also don’t know that in any amount of detail. And that’s okay – there’s so much stuff to learn you can’t possibly ever get to the bottom of it all.
We’re just smart (yet also incredibly stupid), well-dressed apes – but if you were thinking that this sentence would lead to reduced complexity, a ‘and it’s all really very simple…’-point, well, then you’d be wrong. We’re just smart apes, but we’re apes which interact with each other and with our environment. And if you have a closer look at that stuff, it turns out that the interaction patterns that form our lives and our behaviours are so complex that they almost defy belief.
And it gets worse, or better, depending on whom you ask – because there are trillions of other places out there without smart well-dressed apes; places so remote we can’t even imagine the distances involved, but at the same time also places where we don’t even need to go near to understand a lot of what is happening there. Because we through a combined effort as a species have gotten wonderfully good at understanding what’s going on in this remarkable universe we’re a part of. Ignorance is the default state. But it should not be a desired end state. The world gets so much bigger, so much more interesting, once you start to look closer at what’s going on.
So much stuff to learn, to understand, to take with you! The world is an amazing place – allow yourself to be amazed!
I’m sad Feynman died before I ever got to at least have a chance to meet him. He set a good example:
(The last one is a repost, but I love that one.)
The effects of fishing on sharks, rays, and chimaeras (chondrichthyans), and the implications for marine ecosystems
“The impact of fishing on chondrichthyan stocks around the world is currently the focus of considerable international concern. Most chondrichthyan populations are of low productivity relative to teleost fishes, a consequence of their different life-history strategies. This is reflected in the poor record of sustainability of target shark fisheries.
Most sharks and some batoids are predators at, or near, the top of marine food webs. The effects of fishing are examined at the single-species level and through trophic interactions. We summarize the status of chondrichthyan fisheries from around the world. Some 50% of the estimated global catch of chondrichthyans is taken as by-catch, does not appear in official fishery statistics, and is almost totally unmanaged. When taken as by-catch, they are often subjected to high fishing mortality directed at teleost target species. Consequently, some skates, sawfish, and deep-water dogfish have been virtually extirpated from large regions. Some chondrichthyans are more resilient to fishing and we examine predictions on the vulnerability of different species based on their life-history and population parameters. At the species level, fishing may alter size structure and population parameters in response to changes in species abundance. We review the evidence for such density-dependent change. Fishing can affect trophic interactions and we examine cases of apparent species replacement and shifts in community composition. Sharks and rays learn to associate trawlers with food and feeding on discards may increase their populations.”
From the abstract of the study, which I found very interesting. Here’s some more stuff from the paper:
“Large-scale exploitation has led to changes in fish community structure. Fishers tend to remove the largest species first and then work their way down the food chain catching smaller species (Pauly et al., 1998). Consequently, changes in species composition of fished communities may be expected, with small, fastergrowing, and earlier-maturing species predominating. Small species may also be less desirable on the market, and may therefore be subjected to lower fishing mortality (Jennings and Kaiser, 1998; Jennings et al., 1999b). Within the chondrichthyans, the examples for skates discussed above reveal a broadly similar pattern. Similar patterns have also been reported in shark communities: as larger sharks were depleted smaller species proliferated (van der Elst, 1979). The general paradigm is that larger species decline while smaller species predominate.
There have also been declines in diversity associated with increasing fishing pressures, particularly in large predatory taxa (Jennings and Kaiser, 1998). Chondrichthyans tend to be high in the food web (Cortes, 1999) and, due to their greater vulnerability (relative to teleosts), are likely to be the first to decline from fishing. Rogers et al. (1999) suggested that fishing, through the differential vulnerability of elasmobranchs relative to teleosts, is responsible for major variations in fish diversity in the North-east Atlantic. [...]
Discards from fisheries affect the amount of food available to scavengers and thus may be expected to have an effect on certain components of the ecosystem. Although some studies conclude that Australian prawn trawling had few significant, long-term impacts (Kennelly, 1995), about 95% of the by-catch in the Northern Prawn fishery is discarded, and most of it is dead (Wassenberg and Hill, 1989; Hill and Wassenberg, 1990). About half of the discards float and are scavenged by birds, dolphins, and sharks. The other half sinks and is preyed upon by sharks in mid-water and teleosts, sharks, and crustaceans on the bottom. [...]
The predictions of the Venezuelan shelf ecosystem model under a mixed control assumption show that shark depletion could lead to strong and unforeseen changes in the abundances of many species (Fig. 4). According to the model, these changes would be permanent as long as shark populations remain depressed. Surprisingly, not all species whose abundances increased greatly are major prey of sharks. In fact, the species undergoing the greatest relative increases in abundance (croakers, snappers/groupers, grunts, catfish, and other demersals) are all minor components in the diet of the small triakid sharks, suggesting that shark depletion propagates through the food web in a complex way. Some changes are virtually demographic explosions of up to two and a half times the original biomass (i.e. croakers). Conversely, two of the major prey items of the sharks did not increase much in abundance; they even decreased (carangids and small pelagics). Squid and benthic producers, two groups not part of the diet, suffered abundance decreases of about 10% and 15%, respectively. Clearly, the outcomes are not as predictable as one might expect. [...]
Chondrichthyans, by nature of their K-selected lifehistory strategies and high position in trophic food webs, are more likely to be affected by intense fishing activity than most teleosts. The group may in fact be indicators of fishing pressure. There is sufficient evidence from the history of fisheries around the world, both targeting these fishes and taking them as by-catch, of major declines in population size. For some groups, particularly certain skate species and sawfishes, there is mounting evidence suggesting that local if not global extinction is a distinct possibility. This problem is especially acute for species with restricted distributions. The massive and uncontrolled catch of chondrichthyans in the Indo-West Pacific, coupled with the higher diversity and rates of endemism in this region, are cause for major concern. There is increasing evidence that indirect effects of fishing are affecting the composition and diversity of chondrichthyan and total fish assemblages through trophic interactions. Differential vulnerability to fishing exists among sharks and rays and large, late maturing species appear to be most vulnerable. This has caused changes in the community through competitive release, although there is little evidence for species replacement. There is good evidence that selective fishing mortality can lead to changes in growth and juvenile survival for both sharks and batoids, leading to changes in population dynamics. However, the effects of removing large numbers of these top predators on the marine ecosystem are still largely unknown. Attention needs to be focused on this poorly studied group of fishes, particularly in the ecosystem context in terms of understanding trophic interactions.”
1. Aposematism. You know that thing where poisonous animals have very brightly coloured skin to stop predators from eating them and die in the process?
I’ll have forgotten what it’s called next week, unless I reread this post multiple times. My tendency to forget all kinds of stuff I’ve supposedly learned is part of what separates me from high IQ-folks; my knowledge retention rate is much lower. Though I don’t care enough about it to do something about it, like trying to improve my memory.
Interesting related fact: The highest of the ‘fatality to summit’-ratios of the eight-thousanders is that of Annapurna. Also: “Annapurna I holds the highest fatality rate among all 14 eight-thousanders. As of 2005, there have been only 103 successful summit attempts, and 56 lives have been lost on the mountain”. Half of all who climb that thing die yet people keep doing it. The best reason the first solo climber of that mountain could come up with when asked the question why? “I did it for my soul.”
3. Republic of Venice. The ‘history of…’ article has more.
4. Execution by elephant.. Exactly what it says on the tin. A few quotes:
“Hindu and Muslim rulers executed tax evaders, rebels and enemy soldiers alike “under the feet of elephants”.” Yes, tax evaders.
“Some monarchs also adopted this form of execution for their own entertainment.” (remember how it was before the tv? You have to do something to keep the boredom at bay…) [...] “in the Mughal sultanate of Delhi, elephants were trained to slice prisoners to pieces “with pointed blades fitted to their tusks”.“
“The use of elephants as executioners continued well into the latter half of the 19th century.”
5. Bergmann’s rule.
An image post, I’ve put it all below the fold.
Most of All of the images are back from April. Click any image to view it in a much higher resolution. You’re free to do whatever you like with them.
Some beautiful pictures.
I usually employ auditory stimuli when I want to relax, but sometimes visual stimuli work just as well. Click the pictures to watch them in a higher resolution. Here’s the link:
Here’s the link, thanks to Sandmonkey. If you don’t like the music then just turn it off and put on a piece of, say, Debussy instead, the visual imagery is too great to be discarded solely because of the audio.
- 180 grader
- alfred brendel
- Arthur Conan Doyle
- Bent Jensen
- Bill Bryson
- Bill Watterson
- Claude Berri
- current affairs
- Dan Simmons
- David Copperfield
- david lynch
- den kolde krig
- Dinu Lipatti
- Douglas Adams
- economic history
- Edward Grieg
- Eliezer Yudkowsky
- Ezra Levant
- Filippo Pacini
- financial regulation
- Flemming Rose
- foreign aid
- Franz Kafka
- freedom of speech
- Friedrich von Flotow
- Fyodor Dostoevsky
- Game theory
- Garry Kasparov
- George Carlin
- george enescu
- global warming
- Grahame Clark
- harry potter
- health care
- isaac asimov
- Jane Austen
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- Jon Stewart
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- karl popper
- Khan Academy
- knowledge sharing
- Leland Yeager
- Marcel Pagnol
- Maria João Pires
- Mark Twain
- Martin Amis
- Martin Paldam
- mikhail gorbatjov
- Mikkel Plum
- Morten Uhrskov Jensen
- Muzio Clementi
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- North Korea
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- Ole Vagn Christensen
- Oscar Wilde
- Pascal's Wager
- Paul Graham
- people are strange
- public choice
- rambling nonsense
- random stuff
- Richard Dawkins
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- Sun Tzu
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- The Art of War
- Thomas Hobbes
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- walter gieseking
- William Easterly