This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
When we left the volcano Rangitoto two posts ago, I promised more Down Under fern excitement. For the six of you still here, here we go!
Toward the beginning of my hike I saw signs pointing to a kidney fern glen or gully. That sounded *extremely* promising, though I'd never heard of a kidney fern before in my life. But come on . . . a kidney fern? What's that all about? Bet it's awesome. I didn't have time to visit the glen, but it wasn't too long before I spied my quarry on the main trail.
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Here's why they're called kidney ferns. Note that like the filmy ferns, these guys are translucent, which implies they may be only one or a few cell layers thick:
Wow! Would you have guessed these were ferns? I was curious where these ferns might make their sori, or spore-forming structures, and kept my eyes peeled for a lucky break. I was in for a treat. These are the first ferns I've seen that make them in a corona or crown around the edge:
A closeup:
At 1 o'clock and 11 o'clock you can see where a few have popped open and the little red-brown sporangia (remember the Roman-helmet things from the last post?) themselves are sticking out.
Rangitoto had yet another wonderful surprise lying in wait:
Tree ferns!
The first I'd ever seen. Yes, Earth still retains some remnant of the feel of the age of dinosaurs in the form of tree ferns, the first of which evolved long ago in the Paleozoic. I don't know how similar modern tree ferns are to their ancient kin in form and shape, but they make me feel as if I'm in another place and another time all the same.
Here is a beautiful coiled up tree fern frond, or crozier. It's a new leaf getting ready to unfurl, and it's beautiful.
The same name is given to the crook of a bishop's staff that has an identical appearance. In the spring, you can also buy fiddlehead fern (named again for their appearance) croziers at the grocery store in the U.S. for your culinary pleasure.
On a tree fern, croziers can travel a long way before they're finished uncoiling.
Ferns can also have some very surprising appearances. Here's a very primitive-looking (but not necessarily less-advanced) fern I also found on Rangitoto. It just looks like a simple leaf (look at the three simple leaves in the middle of the photo, sprouting from the right).
And the leaf conceals a beautiful surprise:
The sori are scattered about the bottom in a delightfully Cro-Magnon-looking style.
Here's another fern I was curious to flip:
And here's what it looks like on the reverse:
Its sori are all in beautiful diagonal rows.
Finally, there was this oddity, certainly not a fern. Whether a moss or a lycopod, another kind of early-evolving plant that once upon a time sprouted huge forests, I am not sure. Suggestions welcome.
Once I reached the top of the island, we had a beautiful view back down toward Auckland.
Here's a closeup:
I'm told people bungee jump off that needly-looking thing.
On the way down, I couldn't help but notice this:
Forgive me, Kiwis. It made this stupid American smile.