What do we actually see and hear? It may sound like a weird question, but it’s worth considering.
Sound is just vibrations interpreted by our ears.
Vision is simply light hitting our eyes.
Ed Yong’s fascinating book, An Immense World, explores this through the lens of animals.
It turns out that animals have totally different experiences of the world than we do – they see, hear, taste, smell, and feel differently from us. They have access to senses and worlds that are entirely unknown to us.
An Immense World: How Animal Senses Reveal the Hidden Realms Around Us, by Ed Yong
Some animals, like sea turtles or certain birds, have built in magnetic compasses that allow them to automatically follow migration patterns. Some fish communicate through electricity. Even more mundane senses, such as taste or vision, are experienced differently by various species. Mosquitoes taste with their feet, so they know they’ve found a tasty human as soon as they land on one; mosquito repellent works as it’s so bitter to their taste receptors that they automatically jump off as soon as they land on it.
Each animal has unique requirements, and evolution has masterfully tailored their senses to suit their specific lifestyles. Giant squids’ humongous eyes help it see sperm whales, their main predator, from afar. There is a type of beetle which can sense heat from dozens of miles away; it uses this adaptation to find forest fires, where they lay eggs - a newly burned forest is a great place to grow up as a beetle, with abundant food and predators repulsed by the smoke and heat.
This has been one of my favorite books of 2023, which says a lot about it, considering it’s hard for me to get into science books. Yong is a great writer, and the examples are so vivid and interesting that it’s hard not to feel engaged.
Reflections and reactions
One key insight from the book is that the reality we perceive is unique to us. There are colors we can’t see, sounds we can’t hear. While he’s speaking about animals, this obviously applies to people as well. At the end of the day, we all have our own operating systems for viewing the world and can’t really understand how other people truly process or see things. It’s impossible to know what it’s like to be a bat, but it’s also impossible to know what it’s like to be our spouse or friends or coworkers.
There are always tradeoffs. In theory, we (and every species) would have amazing hearing, eyesight, smelling, etc. But this is expensive and takes energy, which could be used to find food or keep us alive. It’d also be impossible for us to take it all in, and sometimes there are advantages to seeing less. For example, there are certain monkey populations where some monkeys are colorblind and some aren’t. Monkeys with better color vision can find more fruits in trees, but the ones without vision are better to find insects on the grounds as they aren’t distracted by color or fooled by camouflage.
Do animals feel pain? This is a contentious issue. There is a difference between pain and sensation. Pain is the unpleasant feeling I get when I do something painful. Sensation refers to sensor cells registering something “painful,” like when I touch a hot stove and immediately recoil. At the very least, animals show a preference for avoiding “painful” things– but can we ever know what they really feel?
Species evolve alongside each other. Male crickets sing to attract mates, but over time, predator flies evolved to be able to hear their songs. As a result, some cricket populations have acquired a mutation that makes their song silent - while harder for them to find mates, this prevents them from being eaten. Evolution is like an arms race or cat-and-mouse game.
Other random cool facts
There is a fourth color: ultraviolet1. We can’t see it, but birds and some other animals can. As shown in the picture above, it allows them to see how flowers “actually” look, which points them to where the pollen is.
Catfish have taste sensors over their entire bodies.
Vultures crash into wind turbines because they evolved to not need to look straight ahead, but simply to the side to see other vultures and down to see their prey.
Scallops have 200 eyes but see in a different way. Whenever there is motion, their eye works as a motion detector and tells the brain “hey, there’s something here” without sending any image. So in a way, it’s sight without seeing.
Whale songs can travel across oceans.
Thank you to my friend Ben for recommending this book.
In addition to red, blue, and green.