spider, feather, frog: 3 little notes on gender (and wonder) in nature
I GOT ON A BIT of a gender kick recently on Instagram, and I blame it on a spider (and a turkey, and a frog)—and also on my endless curiosity. It happened like this:
along came a she-spider
ALONG came a spider the other afternoon, specifically an impressive female garden orb weaver, Argiope aurantia—an extremely widespread species, from southern Canada down to Costa Rica and most of the lower 48 between.
And I say female with a degree of confidence, because of her size (a female of this species can be up to three times a male’s) and also because of the big web she had made.
See that zig-zag stuff in her web? It’s called stabilimenta (word of the day; singular is stabilimentum) and if you get a chance to see the locomotion she gets going to make it, it’s very cool. Whether the zig-zags simply reinforce the web or also help in other ways, such as with prey attraction or advertising to birds not to fly into webs, has been the subject of various research efforts.
what tom left behind
WHAT TOM left behind (left to right, above): one tail feather and one wing feather from an adult male turkey. How do I know where these feathers fitted onto their former owner’s plumage, and that the bird who lost them was a male and an adult? The United States Fish & Wildlife Service Feather Atlas is a cool tool for such IDs. Visit it, and be prepared to get lost in geeky exploration.
One tech note: The search box up top left at the Feather Atlas sometimes doesn’t work for me, so I often start here, on the search page—reachable from the “search scans” navigation button up top, and then just type in a common name like “turkey” or “robin” or even “warbler.” Or I use the “browse scans” button up in the navigation to just have a look around by family of birds (which has the side benefit of teaching me a little avian taxonomy).
If you have no idea whose feather you saw, there is a tool for narrowing your selection by pattern and color and such characteristics.
An important addendum: It is illegal to collect feathers, even from dead birds—a violation of federal law to pick them up and take them home from where you find them. Have a look, take a photo, and leave them be.
A YOUNG frog girl perches on lip of a water-filled trough outside my kitchen door (photo, top of page). I say “girl” because of the size of her typanum, the flat membrane behind her eye that is an external hearing mechanism. A frogboy’s tympanum is bigger than his eye; frog girl’s is equal to or smaller than her eye.
Another tipoff if one is inclined to try to sex a frog is the white throat; boys in the green frog species (Rana clamitans, or Lithobates clamitans), and also in bullfrogs where I live (R. catesbiana or L. catesbeianus) take on yellow throat coloration, especially vivid in mating season. Ribbiting, huh?
These are just tiny bits of marvel that can reveal themselves if we indulge our curiosity outdoors—if we take a few extra minutes to really observe, and ask what is going on and who that is and why, oh why?
learn more about the ‘wild’ in your garden 9/15/18 at my place
I’M HOSTING a workshop on how to up the ante of “wildness” in your garden–more beneficials like pollinators and birds and frogs–on September 15, 2018, in Copake Falls, NY, with an ecologist and field botanist friend to guide us. Interested? More about it on this other page.
just a few good places to look stuff up
- BugGuide.net (insect and spider ID)
- Animal Diversity Web (University of Michigan Museum of Zoology)
- All About Birds (Cornell Lab of Ornithology); just enter a bird name and get a profile with life history, range maps, more
- The Feather Atlas
- Field guides (I have a separate bookcase full of them, including those below)