The Shell Line
Kip the hermit crab has outgrown his favorite shell, and the new one he finds is far too big. Then, one moonlit night, a shell washes up and every crab on the beach gets in line.
00:00Ready?
Hello again. Is your pillow just right? Give it one good squish. [pause] There. Tonight we're going down to the beach, after dark, when the sand is cool and the moon is out. We're going to meet a very small hermit crab called Kip, and a shell that was a little bit too tight, and a line that went all the way along the beach.
00:36A little too tight
Kip lived in a shell the color of milky tea. It had a little swirl at the top, and he had lived in it for as long as he could remember. He liked it. He knew exactly where to tuck his legs, and exactly how to curl up when a seagull flew over. But lately, something was wrong. When Kip tucked in, his elbows bumped. When he curled up, his knees squashed. And this morning, when he tried to hide from a big wave, he got stuck halfway, with his bottom inside and his face outside, and the wave splashed right on his nose. [chuckles] "It's shrinking," said Kip crossly. "My shell is shrinking." [pause] His grandma crab, who was very old and lived in a big white shell with a chip in it, looked at him for a long time. "Your shell isn't shrinking, Kip," she said. "You're growing."
01:38Too big
That afternoon, Kip found a new shell. It was lying on its side by a rock, and it was beautiful, pale pink inside, smooth as a spoon. He crept out of his old shell, which felt very strange and very chilly, and he scurried into the new one. [pause] Oh, it was big. It was so big that when he said "hello," the shell said "hello, hello, hello" back. It was so big that when he walked, it tipped, and when it tipped, he rolled, and when he rolled, he ended up upside down with his legs waving at the sky. Kip crawled back out and hurried home to his old tight shell, and squeezed himself in, elbows and knees and all. "That one was too big," he told his grandma. "It was all wobbly. It wasn't me." "Hmm," said his grandma. "Too big. That's a good problem to have."
02:46The night the shell came
That night, the tide brought something in. [pause] It rolled up the sand, and it stopped, and it sat there in the moonlight. A shell. Not a small one. A big one, big as a teacup, shining. Now, a shell that big was much too big for Kip. It was even too big for Kip's cousins. But word spreads quickly on a beach at night. One by one, crabs came out from under the seaweed and behind the rocks, and they all looked at the big shell, and then they all looked at each other. And then they did something hermit crabs really do. [pause] They made a line.
03:34Smallest to biggest
They lined up by size. Kip was very near the end, because he was very nearly the smallest. In front of him was his cousin Dot, in a shell like a striped sweet. In front of her was a crab called Mr. Barnaby, in a shell with a barnacle on top. And so on, and so on, and so on, all the way along the sand, crab after crab after crab, bigger and bigger, until right at the front, next to the shining shell, was the biggest crab on the whole beach. [pause] Nobody pushed. Nobody hurried. Everybody just waited, in the moonlight, holding very still. "What are we waiting for?" whispered Kip. "You'll see," whispered Dot.
04:29Everybody moves up one
The biggest crab crept out of her old shell and into the shining new one. She turned around inside it once, twice, and settled. It fit. [pause] And her old shell was empty now. So the next crab in the line climbed out of his shell, and climbed into hers. And then his shell was empty. So the next crab climbed into that one. Click, [pause] shuffle, [pause] click, [pause] shuffle, all the way down the line, like dominoes going the slow way. Mr. Barnaby climbed into a bigger shell. Dot climbed out of her striped sweet and into Mr. Barnaby's shell, barnacle and all. And then, there in front of Kip, was Dot's old shell. Striped. Empty. Waiting.
05:27Room to grow
Kip looked at it. It was bigger than his milky tea shell. He could tell, just by looking, that it would be a little bit wobbly. A little bit echoey. "What if it's too big?" he said. His grandma had come up beside him, slow and creaky in her chipped white shell. "Tight means you're growing," she said. "Too big means you've got room to grow into. Neither one is wrong, Kip. It just feels new." [pause] So Kip climbed out of his old shell, quick, quick, in the chilly air, and into the striped one. It was roomy. It tipped a tiny bit, and he leaned the other way, and it stopped tipping. He said, very quietly, "hello," and the shell said, "hello," just once, softly, like it was saying it back to him. [pause] And behind him, the smallest crab on the whole beach, a tiny little thing no bigger than a pea, crept into Kip's old milky tea shell, and fit perfectly.
06:40The quiet beach
One by one, the crabs went home, each in a shell that was a little bit bigger than the one they had woken up in. The line was gone. The moon was high. The waves came in, [pause] and went out, [pause] and came in, [pause] and went out. [pause] Kip tucked his legs inside his new striped shell. There was a bit of extra room by his elbows. He didn't mind. He knew what it was for. [pause] He curled up, and it held him, and the sea went on whispering to the sand. Shhh. [pause] Shhh. [pause] Goodnight, Kip. [pause] And goodnight to you. You're a little bigger than you were this morning, you know. Everybody is. [pause] Sleep well.
- Lewis & Rotjan, "Vacancy chains provide aggregate benefits to Coenobita clypeatus hermit crabs", Ethology 115 (2009): hermit crabs really do wait near an oversized empty shell and line up roughly by size, then swap shells down the line one after another, so one new shell can rehouse a whole chain of crabs.
- Carol Dweck, Mindset: The New Psychology of Success (2006): the idea under Grandma's line, that the uncomfortable feeling of something being hard or new is what growing feels like from the inside.