Sad news today. Two grand ladies who had a strong influence on me have passed away. I can’t say that I knew them, although I heard both of them speak.
Anne McCaffrey died at her home in Ireland. She is, of course, known for her Pern novels, and I didn’t realize until I saw her obituary that The White Dragon was the first science fiction novel to make it onto the New York Times bestseller list.
Lynn Margulis, winner of the National Medal of Science, died at her home in Massachusetts. She’s best known for demonstrating that eukaryotic cells derived from serial endosymbiosis, the fusing of several prokaryotic cells to form the organelles of the eukaryote (and yes, I’m keeping it simple). I don’t think she was the first person to consider this idea, but she certainly was the one who demonstrated it and popularized the concept.
A copy of Dragonflight was the first book I ever had autographed, and I still have it. As a child in a house with a cat named Smaug, you can guess that I ran into dragons early, but I was drawing Michael Whelan-style dragons as soon as I saw the cover of The White Dragon in my parents’ hands. I’ve had a fondness for dragons ever since.
As for Dr. Margulis, she and I both went to the same school, albeit decades apart, and her books (particularly The First Four Billion Years, which I read for fun as an undergrad) introduced me to the concept of symbiosis, something which ultimately became the topic of my PhD research.
Oddly enough, the first book I wrote, Scion of the Zodiac, is in part about symbiosis, and in part about dragons. Thinking about it, perhaps I should have dedicated it to the two of them.
The world is a better place from their lives and their work, and they will be missed.
Filed under: Real Science Content, science fiction, Speculation, Worldbuilding | Tags: interstellar colonization, science, science fiction, worldbuilding
Let’s assume, for the moment, that interstellar travel is possible. Let’s further assume that there’s no magic wand of teleportation or FTL, traveling to another star takes a looong time, and it basically means colonizing your starship (or gaiaspore, if starship is too passe for you). The ship may be Charlie Stross’s hollowed out asteroid, or a comet, or something similarly large, but whatever the ship looks like, the basic idea is that people don’t put their lives on hold for the duration of the trip. Rather, they settle into their ship, and then they (or their distant descendents) settle another world elsewhere.
The two-step is an environmental filter. Many technologies that are ubiquitous on Earth, such as cooking knives or internal combustion engines, are non-starters in free fall (where scissors work better) or in small biospheres (gasoline engines). Consequently, interstellar travelers will abandon quite a lot of Earth’s technology when they live in space. They’ll also certainly invent lots of uses for vacuum and all sorts of high energy particles, but that’s another story.
Anyway, once they’ve made the first step of abandoning Earth tech and its associated culture (no car culture in space), once they get to another planet, they’re faced with a new environment where they have to adapt again. Suddenly they have dependable gravity and a huge biosphere to draw on (or at least, a planet’s worth of resources). In the second step, do they simply adapt spacer culture and technology to meet the challenges of the new place, or do they read through copies of the ancient Wikipedia and start experimenting with, say, gasoline engines again?
There’s a real-life analogy to this process: Polynesia. As the Lapita peoples settled the Pacific, they abandoned things like pottery, weaving, and flaking rock (and possibly bronze metallurgy) as part of their adaptation to living on coral atolls. Once they colonized places like New Zealand, they didn’t spontaneously pick up their ancestor’s technologies, even though they had the resources (such as clay) to do them again. Instead, they adapted their Polynesian tool kits to new surroundings.
There are some subtleties here: for example, Polynesians didn’t just abandon pots because there was no clay on atolls. They were abandoning them before they got to the atolls, because they were switching from cooking over an open fire (where pots are useful) to cooking in an earth oven (where pots are useless). Moreover pots are more fragile than wooden bowls, coconut shells, and gourds. Similarly, they switched from flaking rock edges (on obsidian) to grinding, because grinding works on all sorts of materials, including the giant clam shells used for adze blades on atolls, while flaking just works on glassy rocks. The thing is, adzes work better when they’re ground rather than flaked (whatever they’re made of), the Polynesians also had bamboo (which can be shaped with an adze to make a nice sharp knife), and Easter Islanders figured out how to flake knives on their own in any case. The bottom line is that loss of technology isn’t just about losing the tech, its involves a whole shift to other tools and practices that sometimes makes things superfluous. A society on electric cars won’t be exactly the same as a society built around gasoline cars, because the two vehicles have different strengths and weaknesses.
Getting back to the interstellar two-step, it’s a fun to play as a thought game. If you were leaving Earth for space, what would you abandon? If you were planning on getting your descendents to settle elsewhere, would you have them do: resurrect Earth culture, adapt spacer culture, or both?
Examples of adapting spacer culture might range from using scissors and shears in place of knives, to using air guns instead of gunpowder, to using various cooking techniques that work regardless of gravity, but not gravity-requiring methods such as frying. How about transportation? Art? Agriculture? For example, if they kept goats in space, would you have them bring along cow embryos and the means to grow them to re-establish cattle, or would you rather give them the biotechnology to engineer a giant goat that fulfills most of the cow’s roles in terrestrial agriculture?
What do you think? How would you do the Interstellar Two-Step? I’ll say right off that there’s no right answer. This is a thought game, pure and simple.
Just realized that I should have posted this for Halloween. So instead I suggest using this to start (or end) conversations on Thanksgiving.
Years ago, I came up with a way to objectively test astrology and personal horoscopes. It’s simple, and any experimenter can do it if he or she can find a bunch of willing participants and convince them to spend a few hours rating a bunch of horoscopes. I’ve described my results below, and I encourage other people to try it, as a psych experiment or just for fun.
Experimental Design:
Hypothesis: If astrology is useful, then a person’s horoscope should apply to them more than someone else’s horoscope does. Here, I’m not interested in any purported celestial mechanisms. If a horoscope works as advertised, then a personal horoscope should be more relevant to that person than someone else’s is (or a randomly created horoscope). If this is the case, then it’s worth looking for a mechanism. If the null hypothesis in the next paragraph is right, then there’s no point in looking for a mechanism, is there?
Null hypothesis: subjects will either rate all horoscopes approximately the same, and/or most subjects will find other people’s horoscopes more relevant to their lives than they do their own. I’ll explain why this might be the case lower down.
Method:
1. Find a website that gives out free, nine planet, twelve house horoscopes.
2. Recruit a bunch of experimental subjects. I’d suggest 10, and fewer than five is problematic. Get their birthplace, birth date and birth time information.
3. Compile everyone’s horoscope from the same website. The experimenter should strip out any identifying information (for example, anything that says Libra, Virgo, etc), and the subjects should not see their horoscopes prior to the experiment. Typically horoscopes are printed as a list of paragraph statements, one for each planet and house.
4. If you want, you can even add in randomly generated horoscopes.
5. If you want to make it simpler, you can do one more step. People who were born in the same year tend to have some of the same planets and houses (particularly for the outer planets, which move very slowly). To make it easier for the subjects, you can compile all the paragraphs into one long paper, and have everyone rate every paragraph once. You will have to create a key for which paragraph goes with which horoscope to compile the stats, but this saves on work for the subjects.
6. Have everyone rate EVERY horoscope, every paragraph, on whether that paragraph applies to them or not (I suggest: 1 pt if the paragraph is relevant to the subject’s life, 0 if it’s neutral, -1 if the paragraph does not apply to the subject’s life).
ANALYSIS:
7. Compile every person’s scoring of all horoscope paragraphs. Add up the scores per horoscope.
8. If astrology is true, the prediction is that each person should have scored their own horoscope higher than they scored those of the other participants. The stats for this are a bit more complicated than ranking individual scores, because just by chance, you would expect some people to pick their own horoscopes as the most applicable. Still, it’s not hard, and if the stats look too ugly, simply post how people rated their own and other horoscopes.
9. Collect post-test impressions from the subjects, distribute the results, and have fun talking about it.
When I ran this with 6 subjects with four additional random horoscopes, I got equivocal results (1 person picked their own horoscope, 5 people chose other people’s horoscopes, but with the small sample size, I couldn’t test the hypothesis). I’d love to see other people replicate the test and post their results.
The nice part about this is that it gets around all the tired ideological debates (“it’s not science” vs. “keep an open mind”) and looks at whether printed horoscopes have any perceived relevance to the people who requested them.
What I learned about horoscopes is that, when you read your own horoscope, you tend to focus on the bits that are relevant and ignore the rest. Horoscopes are written to favor this habit: they have a bunch of generally applicable advice mixed very nicely together, much like Forrest Gump’s box of chocolates. However, when you read other people’s horoscopes, what you find is that their horoscopes are also applicable to you. In fact, you may well like someone else’s horoscope better than you like your own. Five of the six people above found that, and one person even preferred a randomly generated horoscope over his own.
Most divination methods work this way: it’s not what is displayed by the cards, planets, coins, whatever, it’s what the person reads into them. This is not necessarily a bad thing, but I think it is better to understand how such a method works, rather than uncritically accept it.
Try it out, and tell me what you think.
Filed under: livable future, Real Science Content, science fiction, Speculation, sustainability, Uncategorized | Tags: future, green, sustainability
This one’s inspired by this NPR story, about sustainability.
What does sustainability look like? In The Ghosts of Deep Time, I have one character say that civilization is cool, quiet, and green, and that’s still my thumbnail for a sustainable city. To unpack that a bit:
Cool. Forests are cooler than grasslands, not because they get less sunshine, but because they catch more of that sunlight and do things with it. Scientists can actually determine how stressed a forest is by measuring how hot it is. Efficiency translates into less energy loss, which means less heating.
In cities, we tend to waste a lot of energy, which is why they are hot. Most of the sunshine gets reflected, or absorbed into surfaces that it heats up. Most of our equipment runs hot, which means we have to get rid of that heat too. A sustainable civilization doesn’t waste much energy, so it’s going to be cool.
Quiet goes with cool. Much of the noise of modern civilization is wasted energy, gone to making sound waves instead of useful work. An efficient civilization is going to be quiet as well as cool.
Green. This is both in philosophy and color. Plants can perform a large number of functions, from cleaning water to providing shade and cooling air. Moreover, we humans aren’t so far from our evolutionary roots that we don’ enjoy having plants around, even if our thumbs are scummy black rather than green. Obviously, a sustainable city will be ethically green as well, but from a simple design standpoint, I think it’s difficult to have a sustainable city without having a lot of functional plants around.
Anything else? Or can we do without one of these?
Just a quick note. For a while, I’ve done the NaNoWriMo (National Novel Writing Month) challenge. If you’ve ever wanted to write a novel, this is the time and way to do it. Go to http://www.nanowrimo.org/ and get involved.
What is NaNoWriMo? Simply a race to write 50,000 words by November 30. That’s 50,000 words of anything. At the end, you call it a novel, upload the file to get your word count verified, and you can scratch “write a novel” off your life-list. You don’t win anything, it’s simply for self-satisfaction and the true sense of accomplishment when you get it done.
Of course it will be unreadable, but that’s not really the point. Think of this as a marathon brainstorm to get ideas out of your head, into a space where you can do something with them. I’ve started my last two novels that way, and it’s a great way to get in the habit of writing 1667.67 words per day. On average. In my case, those 50,000 words have included things like brainstorming, outlining, background research, character descriptions, and actual novel.
Right now, I’m working on the sequel to Ghosts of Deep Time, and I’m behind where I want to be. There’s this pesky little 2.5 billion year gap I need to fill in. Cretaceous or Triassic? The sequel (The Archean Dragon) won’t be done December 1st, but I’ll have 2.5 billion years of something better than what I have now, and I’ll have the novel done (hopefully) a month or two thereafter.
Anyone else joining in? Spread the word. It’s free, it’s fulfilling, and it teaches you things about yourself that you never knew, like the fact that you can write 50,000 words in a month, even though Thanksgiving is in November too. I even recommend it for grad students attempting to finish their theses and dissertations, although in the life sciences, you do NOT need 50,000 words to graduate. It just feels that way. Use those 44,000 extra words to express how you feel about your thesis and your life in epic detail.
Good luck to all who enter.
Filed under: livable future, Real Science Content, science fiction, Speculation, Worldbuilding | Tags: science fiction, starships, sustainability
On Charlie Stross’ blog, I think I called starships gaiaspores, because apparently the term “starship” is passe among the cognoscenti. Or something like that. Gaiaspore does have a certain endearing clunkiness, so use it if you wish. I’m mostly calling them starships here.
But I’m thinking about something a bit different. What comes before the starship? If you remember James Burke’s Connections from the late 1970s, you remember that no invention comes about without a long chain of preliminary discoveries. For living in space, we’re going to need a lot of precursors. What are they?
Let’s start science fiction: how do others see us getting to the stars? The science fiction answers range from, well what we have now (Scalzi’s Old Man’s War, where Ohio hadn’t changed at all in 200 years, except that the elderly now emigrate to the stars) to planetary destruction (Octavia Butler’s Xenogenesis trilogy, where the living, moon-sized spaceships basically ate planets down to the mantle before departing). Charlie Stross seems to break on the large side of the spectrum, talking about hollowing out asteroids and putting slow motors on them. That would require us to digest a few large cities, at the very least.
Assuming a starship is even feasible, it’s going to demand some things we’re currently really bad at, like living at close quarters with nuclear or fusion plants, living sustainably, and living in free fall or microgravity. No culture on Earth lives this way now (although people try it for a few years as an experiment).
So culturally, how do we get there from here? Cultural evolution tends to be path dependent, so it’s not as simple as re-educating the people we have. Imagine turning a Tea Partier into an 18th Century Japanese farmer, or a Papuan highland farmer (both picked because they lived fairly sustainably), and you’ll see the problem. Because of the path dependence, it’s fun to think about where we need to be going before our culture evolves to the point where it can live in space.
What do you think? What do the predecessors to the stars look like? Remember that a pre-starfaring culture has to work on its own merits. Like a bird ancestor, it can’t “half fly.” Those too-small wings have to perfectly good for something else first.
When I wrote Scion of the Zodiac, I cheated on this question. I assumed that we’re going into a post-oil dark age first, and that somehow in that unrecorded time (heh heh) we learned the critical lessons of sustainability that allowed us to go to the stars after the next Renaissance (spurred, I think, by discovering a readable copy of Wikipedia and translating it. No sarcasm there). However, I’ll admit that I was more interested in low tech terraforming than star flight, so I spent more time figuring out how you could survive in an alien biosphere at a low tech level. That last stipulation was so that I couldn’t use magic tech boxes to make life livable. For my “barefoot gaiaformers,” I used three books as my primary references: Bill Mollison’s An Introduction to Permaculture, Jim Corbett’s Goatwalking, and Paul Stamets’ Mycelium Running. Those three books are ones I’d recommend for any post-oil bookshelf, but there’s a lot of good material in there for how to run a gaiaspore. Note that none of these books are mainstream, which is why I think path dependence matters. As for the mechanical side, I’m only starting to think about it.
Obviously, I can babble about this for hours. But what do you think? Can we get to the stars from here? If so, how do we make the connections, and what do the intermediate culture(s) look like? If not, what’s standing in our way?
Filed under: fantasy, fiction, science fiction, Worldbuilding, writing | Tags: novels, science fiction, Time travel, writing
Oddly enough, I’ve been meaning to put this up for over a week. Originally, I was going to wait until I had the book ready for sale, but you know, reality has it’s own agenda. All of a sudden, a bunch of things suddenly erupted onto my schedule like post-rain mushrooms. Smashwords takes a bit of time to publish things, so I thought I’d put the teaser up now.
It’s my second book, and this one is in the spirit of Poul Anderson’s Time Patrol. The title is The Ghosts of Deep Time, and the book contains a novel and a short story.
From the back cover:
“A consultant finds a fossilized pack in the desert, then finds himself back in the Miocene with a criminal gang.
A game warden busts a group of trespassing druids in a wildlife sanctuary. They vanish in a green flash and he loses his job, only to be recruited for something much bigger.
This is the big secret: time travel is easy. There are over four billion years in Earth’s past. The deeper one goes in time, the more alien the Earth is. Still, people have settled most of Earth’s history. Of course they live without a trace, for that is the law of deep time. To do otherwise could create paradoxes, bifurcating histories, even time wars and mass extinctions.
Where there is law, there is also crime. When crimes span millions of years, law enforcement takes a special kind of officer. An ex-game warden can be the perfect recruit. At the right time.”
Here’s a sample. Enjoy! The Smashwords version will be available in a couple of weeks, and a paper version will be available through Lulu late next week. I’ll add links as things progress.
Update: It’s now available as an trade paperback from Lulu in electronic formats (Kindle, Nook) from Smashwords. Amazon is coming in a bit. In the meantime, you can purchase it from either of these two fine companies.
Filed under: livable future, science fiction, Uncategorized, Worldbuilding, writing
Simple topic. A few months ago, I self-published a SF novel called Scion of the Zodiac. I just dropped the price and made the first half free. Check it out.
I posted about it on Antipope, where John Meaney guest-blogged about world building. Since I spoke up about it, I figured I’d better provide a venue, in case anyone wants to comment on it.
Criticism is fine, and constructive feedback is much appreciated. Note that “It’s okay,” “I liked it,” and “it sucks,” don’t really qualify as constructive feedback. I’m trying to make the next one better, after all.
Filed under: fantasy, fiction, livable future, science fiction, Worldbuilding
Wow, I haven’t posted since…Um yeah. Where did April and May go? Right. Living in my secret identity.
Anyway, random short-ish thought. I’ve been finishing up a time travel manuscript, and now I’m figuring out how to sell it.
The one thing (as I’ve noted below), it’s set partially in deep time. This isn’t the killing-Hitler type of time travel, this is getting back into the Paleocene and other parts of the Cenozoic. While I like human history, I see no need to show off my modest knowledge of the subject, besides which, people with real history backgrounds have been embellishing human history for decades. It’s not like there isn’t, oh, 400 million years of other time to explore.
So I’ve been thinking to myself, “Self, one of the biggest problems I have is getting anyone to believe that a livable, sustainable future isn’t, well, chunky, and funky, and terribly earnest, and only available in a limited color scheme, and…well, not much fun, really. We all “know” after all, that dysfunction and sex are what sell, and if everything functions well enough and people know how to keep their zippers zipped, where’s the fun in that?” It’s that whole eating your broccoli-sprouts feeling about a sustainable future. It doesn’t matter how cool and hip the solar decathletes are, how much we know we need to do it. It’s just missing…something.
At least, that’s my thought. So no, I’m not trashing the past, exactly. What I’m thinking about is the question of where do we find our sustainable inspiration. I think it comes from the past. Perhaps from Eden, or Shangri-La, or the hunter/gatherer paradise, or even Lothlorien. Just think about these places, and those long, glorious green shadow of the past reach out and romantically embrace us. Right? As a society, we’re steeped in the mythology of the fall, of paradise lost, of how things used to be better back in the first chapter, the golden age. Even the silver age.
So what better place to put the sustainable future than the deep past, before humans even evolved. There’s something like 400 million years of livable planet back there, long enough for thousands of civilizations to rise, live, and fall. The only catch is that, if such places existed, they must of been masterful environmentalists, because they’ve erased every trace of themselves from the world.
Of course, this only works if time travel is easy. If time travel is easy, they must be hiding it from us, right? What better inspiration to environmentalism than to live the good life, keep the riff-raff of the unenlightened future out.
So that’s my question: not how one goes about hiding a civilization (I figured that one out already), but does it feel better to have that livable future back in the past, hiding from the fossil record? Is it a cute conceit, or could it actually be inspirational for those of us stuck in linear time?
Darren Naish wasted a lot of my time in the last two weeks, not that it was his fault. It was fun, actually. I was looking for a distraction, and I found it in his discussion of protobats. I didn’t (and don’t) believe the model he put up there, because it doesn’t make sense. At one end, there’s a nice, tree shrewish gliding animal, and at the other end is a bat, and in the middle is a flying insectivore with big hands. What happens in between?
• It goes from rear-wheel drive to front-wheel drive, which is another way of saying that the antebat (bat ancestor with no aerial modifications) has the strong hindlimbs, flexible spine, and barely rotating shoulders common in mammalian quadrupeds, while bats have enormously strong and flexible shoulders, highly reduced pelvises, and hip joints that have rotated substantially, such that their knees tend to point outwards or even backwards. The protobat (something with a patagium and presumably some aerial ability) would be a mosaic in the middle.
• It goes from a rigid glider to a powered flapper. I think I saw this problem first mentioned in Grzimek’s Encyclopedia, but I’m probably wrong, and it was a decades ago. The problem that someone pointed out is that a flapping flying squirrel doesn’t glide farther, it falls out of the sky, for two different reasons.
–First, there’s the question of how a flailing patagium generates lift, especially when the trailing edge is being held semi-rigid by the hind legs. It will lose lift because the aerofoil is disrupted, and it is unlikely that the forelimb movement will get air under the patagium any faster.
–Second, gliders tend to have fairly long bodies, with the center of mass in the center. Increasing strength in the arms pulls the center of mass forwards. You can replicate the problem by making a wide-winged paper airplane and adding paperclip or staple weights, and seeing what this does to the plane’s flight characteristics.
Worst, the hypothetical protobat does makes all these structural changes while needing to glide. If I was feeling snarky, I’d point out that this is akin to evolving a helicopter from a glider, and it’s certainly evolving an ornithopter from a glider.
The real problem with these ideas is that the intermediate stages look less able than their predecessors. This seems to violate evolutionary theory, which posits that evolution proceeds blindly, favoring traits that increase (or at least maintain) fitness, traits which will spread through a polymorphic population and eventually take over, possibly through isolation. A flapping, mid-weighted flying tree shrew seems to embody the worst of both worlds, since it doesn’t have the advantages of flight, nor does it have the simple stability of a glider.
So I started thinking. If bats didn’t evolve from something that looked like a tree shrew, how did they evolve? I assume that there are two limits:
1. There are no extant protobats. This supports two ideas. It implies that evolutionary theory is correct. If bats were at a selective disadvantage, there would be lots of non-flying chiropterans around. It probably also implies that protobats had an advantage over antebats as well.
2. We’re pretty sure that bats evolved in the Palaeocene, simply because their fossils show up in the early Eocene. That tells us a bit about the environment in which they evolved. For simplicity, I’m going to say that it looks something like modern Papua New Guinea (there’s a bit of research behind this statement, but it’s not germane. Take it on faith for now).
Designing an antebat
It’s probably instinctive for biologists to think of gliders as the antecedents to powered flyers, but this may be problematic. There are quite a few extant gliders, for example, but how many of them launch with their front limbs? The only group I could find are the freshwater hatchetfish, and as noted in the comments on Naish’s blog, they are jumpers, not properly gliders. However, all flying animals use their forward limbs to propel themselves through the air. To me, this suggests that we may mislead ourselves by assuming that the ancestor of a flying animal looked like a flying squirrel.
What other way is there? Let’s look at bats and bat development. I don’t for a second buy that bat ontogeny exactly recapitulates bat phylogeny, for the simple reason that it doesn’t in humans. Enormous wings need to develop first and fastest, just to function. That said, the developing bat fetus does suggest a few possibilities.
First, their wings are very different than the hind feet. This seems obvious, but one possibility is that protobats looked like the so-called flying frog ( such as Rhacophorus nigropalmatus) where all for feet are enlarged. There’s no evidence for this in bats: their hind feet are much more similar among species than their wings are, and I assume that this has always been true. Antebat hind feet probably look like those of extant bats. Perhaps their front feet looked like those hindfeet as well.
Second, it appears that the bat’s pelvis is splayed even in the embryo. People seem to assume that the bat pelvis splayed to accommodate the growing wing, but there’s no particular reason to think that.
Third, modern bats have a massive amount of morphological diversity in their heads, but that has as much to do with echolocation as anything else. Still, I think it’s reasonable to assume that antebats had a reasonable amount of head diversity, to the extent that different species or morphs may have consumed arthropods, nectar, fruits, and tree gums, much as modern bats do.
So what did I come up with?
Arachnosorex dubius: a hypothetical antebat
Yes, that’s the dubious spider-shrew, and I’ll be amazed if they ever find it. The name describes both how I think it moved and the niche it held. The images above are my crude sketches of the critter.
In constructing this antebat, I started backwards. What if, rather than the patagium coming first, the hip and shoulder alterations came first?
Are there any animals that have powerful front shoulders and outward pointing knees, and second, are there any advantages to this configuration? Bats have these characteristics, (as do spiders and other non-mammalian animals). Many bats are quite good on vertical surfaces, even ceilings, and they cling well. Something like a vampire (Desmodus rotundus) moves well on the ground, on walls, even on rough roofs, and can launch itself into the air using the power of its forelimbs. The advantage of those backwards pointing hind feet is that they make excellent grappling hooks. An antebat with strong forelimbs and backwards pointed hindlimbs would be quite agile on a variety of surfaces, whether face up, face down, or sideways. However, it gives up some speed for this maneuverability (since it gives up that characteristic mammalian gait, the gallop), so the antebat would be limited to areas like tree-trunks (on the bark or inside a hollow tree), on thin branches (especially the underside of branches) and in caves—in other words, places we find bats now.
This satisfies the first criterion, that bats outcompeted their predecessors. Here I’m suggesting that antebats exploited the same types of food sources as bats do now. Since bats are faster (through flying) than antebats, bats also have a comparative advantage. Additionally, these types of habitats were available in the Paleocene, so it satisfies the second criterion
From nose to tail: the spider-shrew’s head is based on a primitive fruitbat, with a smaller braincase but still well-developed eyes. The forelimbs are well developed, but there is little enlargement of the hand. The hindlimbs are splayed, and the spider shrew overall has a semi-sprawling posture. However, it can move effectively on the ground. The tail is thin and fairly stiff. Its primary function is to act as a support when the antebat is climbing.
Instillator hypotheticus: the dropper, a hypothetical protobat
This “hypothetical dropper” was inspired by a fruitbat photo I found on Flickr. In this case, the patagium is developed, but I see no reason why it should have a hairless patagium.
Here I suggest that antebats became protobats by developing long-distance jumping and falling as an efficient defense and as a way of covering long distances. This lifestyle change hinged on developing more powerful forelimbs and better vision (echolocation evolved after bats flew, according to the fossils). While yes, I’m suggesting a gliding intermediate, in this case, I think it’s likely that protobats powered their takeoff jumps with their forelimbs, not their hindlimbs. They saved on weight by making their bodies more compact and their limbs longer, as seen in modern bats. Probably finger elongation started initially as a way of increasing patagium area (as here, with the dropper), and protobats early on developed the folded wrist we see in modern bats, effectively climbing on the backs of their wrists, with their thumb claws providing the support of the five claws of the antebats. It’s also possible that the uropatagium developed with the arm membrane, giving a “three-winged” form to glide with before ultimately developing into the bats we know today. The advantage of the three-winged form is that there is a separate wing structure that, combined with the highly developed shoulders the protobat inherited from its antebat ancestors, can lead to ultimately to powered flight. The more Instillator develops its forelimbs, the better it does.
Diet wise, I suggest no change from antebats to protobats. The protobats ate the same food as their ancestors did and their descendents will. As with the spider shrew, this satisfies both limiting criteria.
