One and Done

Winter has been really slow in relinquishing its grasp this year. The snow just won’t disappear and the lakes have yet to thaw. Still, regardless of the temperature, spring marches on. The days get longer, the quality of light and the colour of the sky changes and the birds start to return.

One of the first to get back are the Canada Geese. I usually hear my first unmistakable ‘honk’ somewhere around the end of March. It’s an event I always look forward to. For me, it means that regardless of what it might look like outside, spring is on its way.

They’ve been back for a while now and most have settled in to nest. Canada Geese are a ubiquitous bird, common just about everywhere in North America, so common in some places that they are regarded as pests.

Being so universal, they often go unnoticed, just another part of the everyday landscape that make up our lives.  However, if you slow down and take the time to really consider these big, sometimes brash birds, you’ll discover that they’re really quite fascinating.

Canada Geese have a strong affinity for place, at least females do. Female geese return to where they were born to rear their own young. It makes sense at an evolutionary level when you think about it. If her parents successfully raised her there, then the chances of her having her own brood there are pretty good.

The next problem, then, is finding a mate. If she were to choose one on her breeding grounds, they would end up with a pretty shallow gene pool. Over time, each population would have become very isolated genetically. However, if you’re a goose, there’s another place to look for companionship: down south. Their wintering grounds are like Daytona Beach at spring break, thousands of geese from all over converging on locations along the southern US to fatten up and mingle. A young female goose has a lot to choose from there.  Once she finds the gander she’s looking for, he’s in for a trip back to her home waters every spring for the rest of his life.

Yes, Canada Geese mate for life. This detail of their natural history is probably why both males and females look alike. Unlike ducks, where males have to get out there every spring and attract a female using flashy colours and footwork, geese are a sort of ‘one and done’ kind of species. Over their evolutionary history they’ve apparently lost the need to impress each other.

While he might not wow his mate with dashing looks, male Canada Geese are very devoted partners. With the nesting season started, females have hunkered down to wait out the 28 days it takes for their eggs to hatch.  After laying one egg a day until the clutch is complete, she spends about 23 of the 24 hours in a day keeping them warm. Although he doesn’t share incubation duties, the gander takes up the role of sentinel, guarding his charge with the same diligence that she gives to her role. If any potential threat – raccoon, weasel, coyote, unsuspecting hiker- gets too close, he will bear down on them, wings flapping hissing viciously, beating back the intruder.

So, if you find yourself hiking through goose country, keep an eye out and prepare to duck and cover.

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You know, that sounds kind of dirty …

GymnospermI spent quite a bit of time, several years ago, teaching first-year biology labs and when this word came up in the botany section, it would always draw a few muffled snickers from the crowd.

It’s not really all that surprising. Gymnosperm is kind of a funny word; makes me think of some smarmy guy who hangs out at fitness centres, trying to pick up women. Of course, it’s nothing of the sort. Like many scientific terms, it is of Greek origin and basically means ‘naked seed.’

In technical terms, Gymnosperms are a group of seed-bearing plants whose seeds are not contained within an ovary.  The most commonly-known members of this group are the conifers. Here in the north woods, we have a lot of different gymnosperms: spruce (pictured here), pine, tamarack and firs.

So, what exactly do they mean by naked seeds?

In other vascular plants, like flowers, broad-leaved trees and pretty much everything else out there but mosses and ferns, developing seeds are protected inside a closed chamber called an ovary. Instead, gymnosperm seeds are formed on specialized leaves known as sporophylls, which ultimately become the scales of the cones we know so well. Although they are somewhat protected by cones, the scales usually hang open, leaving the seeds exposed, naked.

The rest of the seed-bearing plants out there do things a little differently.  They fall into a group known as angiosperms. In these plants, the seed is kept safe and sound inside the aforementioned ovary, which, once fertilized, becomes the fruit of the plant. As we all know from experience, that fruit comes in all manner of shapes and sizes from the winged seeds of a maple tree to a giant watermelon.

So, what’s the difference? Why should having a naked seed matter?

Having your seeds exposed makes you more vulnerable to the effects of the elements. Seeds that are out in the open are much more likely to dry out or be damaged in some other way. By keeping their seeds inside a protective core, angiosperms can withstand a wider scope of environments, allowing them to exploit more niches. This is why angiosperms have diversified into the most successful group of plants in the world, with possibly over 260,000 species.

Still, gymnosperms have been very successful in many places. Look at the boreal forest. In its northern reaches especially, they are the dominant tree species. The tallest living plant and the oldest single living organism are both gymnosperms. It’s all about making the most of what you have and when you do that in the right environment, you can’t help but flourish.