Thursday, July 29, 2010

Gangly games


When you were a child, did you ever play Red light/green light?

It's one of those backyard games where everybody lines up, except for 'it' who stands, back turned, at the far end of the yard. The players try to creep up and touch 'it' without being seen to move. 'It' can swing round at any time, and if he/she spots someone moving, that person must go back to the starting line.

Well, I've been playing Red light/green light for several days.
And I'm always 'it'.

No, I haven't suddenly developed a passion for amusing small children; in fact, my playmates are considerably bigger than I am.

It all started when Bugbears decided to sleep for several nights at a termite mound located on an open, grassy knoll. With the chilly nights, the mongooses like to start their day slowly, lounging around the mound for several hours, soaking up the sun, grooming and playing. As a result, I've been spending quite a lot of time lounging around there too.

Now, open hilltops are the favoured haunt of mother giraffes; it's easier to spot someone sneaking up on your calf. But when you munch leaves, open grasslands are a bit of a bummer, so giraffe Mums deposit their young in a crèche - tended by just one or two adults – before stepping out for a bite to eat. One such crèche, of up to six gangly calves, has been whiling away its time near Bugbears' mound.


When I first arrive in the morning, and sit down to observe Bugbears, all the giraffes watch me from a distance. Within moments, the adults return to nibbling treetops, but the youngsters keep staring intently. Every time I glance back at them, they're all lined up gawking. Although they're always standing perfectly still, legs splayed out and necks very erect - clearly poised for flight - they're appreciably closer than the last time I looked. This goes on for around 20 minutes, and as they silently creep closer and closer, I begin to feel unnerved. They could be teleporting for all I know; I can almost hear the Twilight Zone music.
Eventually, when they're only about 8 metres (25 ft) away from me, someone suddenly loses their nerve and they all whirl around and galumph away. Of course, this loss of courage is marked by an immense crashing and thundering, which makes both me and the mongooses jump in fright.
Once the young giraffes have recovered their composure (and I'm sure they're all giggling in a silent giraffey way), the whole game starts over again.


Three of the culprits.

I try to be tolerant. I figure giraffe calves deserve a certain amount of leeway: growing into a 4.5 metre stilt-walker isn't easy. By the time these guys reach adulthood, they'll have had to grow an immense heart (weighing 11 kilos, and measuring 0.6 m long) just to get blood up to their brain. And their gushingly high blood pressure (twice that of the most cholesterol-clogged human) is a constant peril; their brain only avoids damage by hiding behind a special bed of capillaries that diffuses the spurting flow. On top of this, giraffes need to grow lungs eight times bigger than our own, just to get a breath of fresh air. If we tried to use a two metre long windpipe, our lungs would draw in and exhale the same stale air, over and over, until we asphyxiated.


Dad checking his charges. The lower legs of giraffes have extremely tight skin to prevent fluids pooling at their ankles, and the blood vessels are deeply internal so minor wounds don't result in high-pressure blood spurting everywhere.


Apart from these logistical hassles, giraffes (like most of us) have inherited all sorts of design flaws from their forebears. Take their laryngeal nerve, which runs from the brain to the larynx (a distance of a couple of inches). In mammals, this nerve casually loops through the blood vessels near the heart before heading to the larynx. While this is a tenable route in 'normal' animals (including the giraffe's squat ancestors) when you add neck-extensions, it becomes absurd. The giraffe's laryngeal nerve zips two metres down its neck, loops around the heart and then zooms all the way back up again to the larynx. No wonder giraffes don't say much.

After an hour or so of Red light/green light, the little giraffes at Bugbears grow weary and wander off to lie down in a cluster in the long grass. They usually sit with their necks erect and their horn-topped faces just showing above the grass. Giraffes are the only animal to get their horns in the womb. No, your concern for Mum is misplaced; the horns are made of cartilage and lie flattened against the calf's skull until after it's born. It's the newborn you should be sympathising with: mother giraffes stand up to drop their calves. Literally drop. Can you imagine a ruder introduction to the world than plummeting two metres to the ground? It's enough to make anyone's horns stand on end.

Refuelling stop. Like all ruminants, giraffes have a four-chambered stomach for breaking down vegetation, but when a giraffe calf suckles it stimulates the opening of a special groove within its stomach which shunts the milk past the rumen (fermentation vat) so it's digested immediately.


I must admit that very young giraffe calves - although undoubtedly cute - give me the creeps. They remind me of plesiosaurs or strange sea monsters because their necks move with complete snake-like flexibility. A giraffe's neck is made up of only seven vertebrae (like yours), but (unlike yours) each one is linked to the next via a ball and socket joint (similar to your shoulder joint). This allows movement in almost every direction (like your arm). Although this wondrous flexibility isn't especially noticeable in adult giraffes, whose neck vertebrae are almost a foot long, in stumpy-necked calves it's utterly alarming!

Maybe tomorrow Bugbears will decide to sleep in a different termite mound, and the giraffe creche will have to find someone else to play with.

 Recent research on captive giraffes has found that the species uses infrasound (very low frequency) calls that are entirely inaudible to humans.

13 comments:

  1. I sure hope that you are writing a book of your observations, research, and adventures. I would get a copy as soon as I could, and tell everyone I know about it. You are certainly a very gifted nature writer.

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  2. That was a wonderful post. Yes, you certainly have experiences and knowledge worthy of (at least one) book.

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  3. I agree wholeheartedly with the above .... in the meantime, can I be your water carrier or something? I'll even put up with burrs and lizards behind the refrigerator, but don't dump cat litter on me!

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  4. A stunning post again Lynda. There is nothing more curious than giraffes, especially when young. At the lodge where I worked, I would walk the 1km or so to work and back and there was one adult who would peer at me through the bushes the whole time. When I disappeared for a moment out of his sight behind a tree or something, he would actually move in order to see me again. :) There were other too but none doing the staring bit. How wonderful it is to have all these experiences.

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  5. John,
    Thank you for the encouragement, but don't hold your breath. I think writing is something I should do when I'm too old and doddery for field work (not that it's that far off!).

    Hugh,
    I'm glad you liked the post. Accumulating knowledge and experiences is much more fun than writing about them!

    Elva,
    How about being a porter? You could follow me about burdened with a fine, bone china tea set (for my morning cuppa) and we could pretend we were in 'Out of Africa'. No guarantees about the cat litter, though.

    Actually, I'm looking for someone to house-sit for two weeks at the end of Sept; maybe you should just pop over...

    Joan,
    Yes, I agree. I think giraffes are the busybodies of the bushveld. I've had the same experience as you describe, and I've seen them idly following a baboon troop in the same way ("primates are funny things, aren't they George").
    I'm always just really thankful that they've kept their ancestors' I'm-a-vulnerable-little-antelope mindset. I hate to imagine the damage an aggro giraffe could do.

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  6. It amazes me when these animals bend down that their eyes don't pop out or something and I have learn t something today about the babies Horns I didn't know that :)

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  7. That sounds like such a delightful experience. I never knew that giraffes left their calves in nurseries. I have often seen it with Impala.

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  8. So wonderful giraffes!! Great picture and post.
    Thanks for visiting my blog:-)

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  9. Philip,
    A giraffe's jugular vein is fitted with hefty check-valves that stop the blood rushing back to its head when it bends down and allows its eyes to stick firmly in place!

    Max-e,
    The nurseries I like most are those of Nyalas. I sometimes stumble on a whole batch of little calves snugged down in the thickets along the creek. In the cuteness stakes, baby nyalas beat Bambi hooves down.

    Spiderdama,
    I'm glad you enjoyed the giraffes.

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  10. Hi Lynda

    My mom loves giraffes!

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  11. Kristen,
    Giraffes seem to be a favourite of lots of people. I love their coats, especially the almost black colour of some of the older males.

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  12. We once saw a giraffe giving birth it was amazing to see it!

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