Tangent: I love the expression, “Can’t swing a dead cat without hitting a…” Where did that come from? Did people ever swing dead cats? If so, I assume you’d swing it by the tail. I’ve actually done 2 fun things with this expression. The first is translate it Spanish: “No se puede columpiar gato muerto sin golpear…” I used it once it
The distance from the center of my chest to the center of the palm of my hand, when outstretched to the side is roughly 3 feet (I’m 6’2”, and have 34” sleeve.) I’ll assume that the rough length of a cat from tip of the nose to the point of the tail where I could get a firm grip (maybe 4” behind the tip) would be about 2 to 2 ½ feet. But as I swung the dead cat, the centrifugal force might cause it’s forelimbs to extend out beyond the tip of its nose. Unless of course the dead cat had in fact already stiffened up, in which case the forelimbs would probably remain locked in position.
In any event, let’s assume that the distance from the axis of rotation (center of me) to the farthest point of the swinging cat is approximately 1.75 meters. (I’m about to do math, and math is easier in metric.) That would make the swinging circle approximately 11 meters in circumference, and would cover a 2-dimensional area of approximately 9.6 square meters.
Now a square kilometer is 1,000,000 square meters. If we divide 1,000,000 by 9.6, that means that it order to hit something- on average- by swinging a dead cat, that something would have to be present in a density of at least 104,167 per square kilometer. Now if we say that the
OK, so actually you can swing a dead cat without hitting a hummingbird. But I am telling you, there are a lot of hummingbirds around right now. Wednesday morning before work I rode the Pipeline trail in
Tangent: With Pipeline opening up, I’m finally able to mtn bike through trees other than Gambel Oak and Bigtooth Maple. Upper Pipeline takes you past Curlleaf Mountain Mahogany (pic right), White Fir and Douglas Fir. All cool trees, all to be blogged about in the coming weeks.
Hummingbirds are of course super-weird, super-unique and super-cool. They’re almost like the Joshua trees of the Avian world. There are endless studies, articles and web pages dealing with their unique flight motion (way different from any other bird, but different from any insect as well) their metabolisms and astronomically high caloric requirements, their migration patterns, coloring and much more. They’re endlessly entertaining to watch, pleasant-sounding to hear, and easy to attract (with feeders.)
Hummingbirds are Nectivores, meaning that they eat nectar, and it’s thought that they co-evolved with many of the flowers they both pollinate and feed upon, which tend to be red, orange or pink. (Flowers which are pollinated by birds are called ornithophilous flowers.)There are over 300 species of hummingbird in the world, in 136(!) different genera all(?) native to the Western hemisphere. Nobody’s exactly sure how long hummingbirds have been around- they fossilize poorly. But genetic analysis indicates that they diverged from their closest non-hummingbird relatives somewhere around 35 million years ago.
Despite the large number of hummingbird species, in
The Black-Chinned Hummingbird is probably the most common
The Broad-Tailed Hummingbird males (pic left) have red-feathered breasts and green backs. The females (pic right) have black and white breast feathers, green backs, and rust-colored sides.
With both these species, in nesting season often the females stick to wetter areas, like canyon bottoms, while the males hang out higher up on the drier hillsides. (So if you hear but don’t see hummingbird, where you are might give you some idea of who’s buzzing you.) The reason seems to be thermal inversions. Females attend the nest/eggs; males don’t. At night, cold air settles into canyon bottoms.
Tangent: This night-time inversion is super-obvious if you ride or hike the upper
The males, who aren’t “tied” to the eggs, can save major calories during the night (estimated as much as 15% difference) by flying just a bit uphill to spend the night.
Earlier this week I had to buy a new set of pedals for my road bike. At the shop I deliberated (OK agonized) between two sets of pedals- one that cost $100 and one that cost $200. The difference was a total of 40 grams- 20 grams per pedal. Weighing the pedals in my hands and noting the negligible weight difference, I realized I was being silly and bought the cheaper pair. The next day I was thinking about hummingbirds and realized that the weight difference in each pedal between the $100 and $200 pairs was equal to 6 adult hummingbirds. All that complexity and function and beauty- a creature that can fly, hover and maneuver like no other, and migrates 1,000+ miles twice a year- engineered into just 3 or 4 ounces. That’s a beautiful package.
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