Monday, December 26, 2022

Why on Earth are flowers beautiful? (2018)

Image: Flowers, by Alvegaspar CC BY-SA 3.0 via wikimedia.org

If you watch science documentaries like Nova or The Nature of Things, you might get the feeling that what’s most exciting about science is all the questions scientists have answers to – all the things we’ve learned about how our universe ticks.  (It’s built right into the title of The Nature of Things.)  But what I love most about science, and especially biology, is how easy it is to ask a question that we don’t have the answer to.  Why are there so many species of beetles*, but so few of snakeflies?  Why does life use a basic set of 20 amino acids, not 18 or 26?  And one that has me completely stumped: why on Earth are flowers beautiful?

“Why are flowers beautiful” might sound like a trivial question, but I don’t think it is.  Across most human societies, most individuals find that looking at flowers gives them pleasure.  We spend billions of dollars on this, of course, sending each other flowers** and planting them around our homes.  If we plant enough of them, it’s a civic and tourist attraction (here’s one I’m involved with).  Millions of people all over the world belong to clubs whose aim is to breed, grow and display slightly different flowers from the ones we grew last year.  And these things are (mostly) not true of the other bits of a plant (“I love you, honey, so I sent you some roots”), or of amphibians, or bats, or stainless-steel fastener hardware.

 We know why flowers are showy, of course, but that’s not the same thing as knowing why we consider them beautiful.  Flowers are showy because they need to signal their availability to pollinators.  Wind-pollinated flowers, like ragweed or corn or oak flowers, don’t need to be showy, and they’re often small and greenish.  We generally don’t consider these beautiful, so it’s probably safe to say that showiness is necessary for beauty, but it isn’t sufficient.  We know showiness it isn’t sufficient for beauty because flowers are also showy via their scents, for exactly the same pollinator-advertising reason  – and we do not consider all floral scents beautiful.  Some flowers speak to their pollinators with odours of rotting meat or dung, and we haven’t decided that we love that language of flowers.

I was motivated to write about flowers and beauty because of a coincidence.  Over just a few weeks, I happened to read three different arguments about why flowers are beautiful – and I didn’t believe any of them.

The first argument (and I can’t remember where I read it) was that our hunter-gatherer ancestors evolved to feel pleasure in seeing flowers because they were a cue for finding fruit – and finding fruit was necessary for survival.  It’s probably fairly obvious why this can’t be right.  Lots of flowers signal the future availability of inedible fruits, or even highly toxic ones, and we find those flowers beautiful too.  And why not simply evolve to find fruit beautiful?  We find some fruits beautiful, to be sure, but not breadfruit or lychees or – well, it’s a long list.

The second argument comes from an otherwise extremely enjoyable book called Wonderland: How Play Made the Modern World, by Steven Johnson. (You might be more familiar with his earlier How We Got to Now, which was the basis for a PBS television series.)  Johnson argues that a wide variety of things – including games, music, coffee, and spices – are enjoyable for no particular reason other than that they’re surprising.  This suggests (and perhaps I’m extending Johnson’s argument further than he would) that flowers are beautiful because they stand out, because they’re so visually different from other elements of our landscape.  But this argument founders quickly: it’s easy to come up with surprising things we don’t enjoy at all.  A flower that smells like rotting meat is pretty surprising.  So was the Elephant Man; and to our shame as a species, we considered him riveting but not beautiful.

The third argument was developed at length by David Deutsch in The Beginning of Infinity: Explanations That Transform the World (p. 353ff) Deutsch argues that some aspects of what we find beautiful are subjective and learned, but that there is nonetheless an objective quality of beauty in the universe.  Deutsch argues that flowers needed to evolve signals to reach their pollinators, that these signals needed to work on a wide variety of pollinating species, and that the easiest way to do that was to evolve signals that conformed to “objective standards of beauty” .  But this argument doesn’t hold water, either.  Are we to argue that some flowers lure pollinators with the smell of rotting meat because that’s a component of objective beauty?  And what about preferences?  Perhaps it’s true that most humans find most flowers beautiful – and even more or less agree on which are most beautiful, as we should if there’s an objective beauty that can be approached more or less closely.  But pollinators have preferences, and they don’t agree about them: what’s an attractive flower to one bee may not be to a different bee, or to a hummingbird or a fly or a beetle.  That’s incompatible with the objective-beauty hypothesis.

What these arguments have in common, I think, is that they’re made by people who don’t really know that much about flowers (Deutsch, for example, is a physicist and amateur philosopher; Johnson’s background is in semiotics and English literature).  Any explanation for why flowers are beautiful is going to have to draw from multiple fields: from evolutionary biology, plant ecology, cultural anthropology, and human psychology, as a start.  We should be skeptical of any explanation of floral beauty proposed by a psychologist who doesn’t know about pollinators – but just as much, by a biologist who doesn’t know much psychology or cultural anthropology. This is, of course, just one flavour of the more general argument that we need thought, and education, and research, that breaks down disciplinary silos.

And now it’s time to admit that, like Arlo Guthrie in Alice’s Restaurant, I’ve pulled a bait-and-switch on you***.  I’m not really talking about flowers.  I’m talking about climate change.  Human alteration of climate, through release of fossil-fuel CO2, is very probably the most serious problem facing our species. It’s a big problem but an entirely solvable one.  Solutions are all around us – but in one important sense, they’re offered in excess.  We hear about the latest whiz-bang saviour all the time, and while it’s good to explore lots of different ways to take action, we need to do so with some thought.  What’s true of floral beauty is true, in spades, of climate-change solutions.  I can pretty much guarantee the nothing proposed by an engineer without partners in biology, economics, and the social sciences won’t solve our CO2 problem (take that, enhanced weathering).  I can also guarantee that nothing proposed by a biologist or a climatologist without full consideration of engineering and economics will solve our CO2 problem.

So solutions to climate change, like answers to the floral beauty conundrum, are harder than one person’s bright idea.  This doesn’t mean we should indulge in a nothing-will-ever-work kind of paralysis.  What it does mean is that we need all hands on deck – biologists, climatologists, engineers, economists, politicians, the whole nine yards – not so that each can propose their own solutions, but so they can come together to deal with the fact that every solution has to work in a complicated world.  The easy fix will always grab headlines, while the real solutions will be complicated and depend on partnerships.  Structures that encourage formation of those partnerships, and initiatives that fund them, are critical.  It’s too bad they don’t grab headlines.

© Stephen Heard  September 18, 2018


 



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