Tag Archives: Metabolism

A Life On The Edge

Imagine yourself a hummingbird. First and most importantly you’re plumb adorable. More clinically, at up to 80 strokes per second, your wingbeats alone are the envy of birds everywhere. It’s not just the frequency of flapping that causes a flap though, your circular wing motion allows you to do things impossible for other birds. You can hover, zip sideways, and most impressively, fly backwards–a feat enjoyed by no other bird. You’re fast too; on a straight shot you might be able to reach a speed of 30 miles per hour (approximately 50 kph) and twice that in a dive. You have a pretty impressive cardiorespiratory system to support all this too. Your heart might beat as fast as 1250 beats in a single minute and you take 250 itty bitty sips of breath in the same amount of time. You put Arnold to shame too; your pectoralis muscles make up 25 percent of your entire body mass. You are totally pumped up–in your chestal region at least.

Pretty cool right? Maybe not. All of this crazy activity comes at huge cost metabolically. To support all this motion and cardiorespiratory frenetics you are ravenous. You must eat more than your body weight in nectar each day. It’s a good thing you can hover, zip and zoom because you need to visit hundreds flowers to get that amount of food. Flowers are well, miserably mundane necessities. So massive are the demands of your ravenous metabolism you can only survive a night’s sleep without food by entering into torpor–bird-style hibernation. Worse than that, you will spend every moment of your life just an hour or so away from starvation. Think about that. Every second of your existence is a life on the edge of certain death. Poor hummingbird-version-of-you; not so cool now are you?

On the upside, you’re still plumb adorable.

 

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