Last
week we were at Pefki, the village of the pines where, somewhat
surprisingly, there weren't many pine trees to be seen. There is
however quite a magnificent pine forest a little to the west, just
past the village of Agios Stefanos which brings us round full circle
on our upland village tour of east Crete. Agios Stefanos, or Saint
Stephen would have been my personal saint, had I been born here in
Crete but I must confess that I had to look him up because apart from
the fact that Good King Wenceslas had a predilection for musing out
of his bedroom window on said saint's feast day I knew nothing about
him. Turns out he was a clever fellow who managed to prove, by
theological argument, that Jesus upheld the precepts of Judaism
better than the Jewish elders did. Clever, but not wise, seeing as he
was on trial for blasphemy by those same Jewish elders at the time.
They sentenced him to be stoned to death. Incidentally this gave us
two important precepts which still hold true today: one, never
conduct your own defense and two, nobody like a smart-ass.
But
I digress. Apart from exploring the pine wood itself I noticed a
beautiful glade when I passed by the other day, absolutely carpeted
with wood sorrel, windflowers, and other small anemones which looks a
delightful place to start. Here we are and I see that the honey bees
are queueing up for nectar. We've talked about pollination before of
course but while we're surrounded by pine trees and looking at
flowers it makes you wonder how we got from one to the other. If you
look at the centre of the windflower (just move the bees out of the
way a second) you can see the female organ, the carpel, surrounded by
the male organs, the stamens. Pine trees have carpels and stamens too
but the key point is that they are separate. There are female cones
that you see all the time and male cones that appear (here in Crete)
in the spring (see Evolution:
Top to Bottom for pictures). Somewhere between 130 and 160
million years ago a particularly enterprising pine flicked a genetic
switch, combined the male and female parts into one structure and the
world of flowering plants was born. Since then flowers have done a
lot of experimenting with some going back to having separate male and
female flowers on one plant, some producing different male and female
plants and various shades of sexuality in between.
So
that's the flowering plants but where did the pine trees come from?
We've got a little shady gully feeding the glade and I think that the
answer may lie up there. Come and meet the ancestors. In here amongst
the shady rocks we have a few ferns. These first appear in the fossil
record some 360 million years ago which is a heck of a long time just
sitting about being a fern. Ferns reproduce by means of spores which
you can see on the underside of the leaves, male and female, which
require external moisture to get together. The breakthrough came with
wrapping the spores in a protective coating and providing them with
internal moisture and this was the origin of the seed. How long this
mutation had been going on in various individuals is anybody's guess
because as long as ferns had a moist environment seeds weren't
needed. But around 300 million years ago when the Earth's land masses
were having one of their little huddles called Pangaea there were a
lot of arid bits where spores couldn't germinate but seeds could and
the seed plants came into their own.
Where
did ferns come from? Come and meet the bryophytes; mosses like these,
along with similar looking hornworts and liverworts. The most obvious
difference between these and the ferns is their size. Mosses are
perfect little plants but their size is restricted because they lack
the internal vessels needed to transport water. This was another
little genetic tweak that proved useful some 440 million years ago
due to falling levels of carbon dioxide in the atmosphere. Plants
need CO2 to photosynthesise but when you let it in, you
let water out and there's the nub of the problem. When CO2
levels are low you have to keep your pores open longer. You either
grow low and close to the water or you develop a way of moving the
water. The bryophytes that solved the problem developed into the
ferns.
Now
if we had some water in this gully we might have found some Chara as
we did in the
Dew
Ponds of Katharo. Chara
is a green algae and it is from these that the early bryophytes
evolved. Some of the green algae went on to become bryophytes, some
stayed as green algae and others went a completely different route
and set up a symbiotic relationship with fungi creating a whole new
group of organisms called lichens such as this sunburst lichen,
Xanthoria
parietina, which
is a combination of a fungus and a green algae called Trebouxia.
So
with that little round-up of how algae became bryophytes, became
ferns, became pines, became flowers, we end our tour of the upland
villages of East Crete. From here, if you own a rugged vehicle you
can continue along the rough road back to Stavrochori
or
return to Agios Stefanos and turn right in the village to get back to
the coast road at Makry
Gialos.
The
Extra Bit
Personally
I think we'll opt for the latter option and pop into Dasakis, a
lovely little taverna (now open all year) at the entrance to
Butterfly Gorge. We can spend a pleasant hour chatting around the
wood stove whilst admiring a pair of Muscovy Ducks in the car park.
Next
week we'll be starting a whole new walking tour in the hills above
Koutsounari. This is new territory for me so we'll be exploring it
together and who knows what we'll find up there.
Photographic
Bit
Many
of you have asked
me
what photographic equipment I use so for details of aperture
settings, shutter speeds etc. my pictures will be on Flickr
within
a few days and that has all the geeky stuff. Pictures
were edited with FastStone Image Viewer and combined with Microsoft
Paint.
*********************************************************************
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Interesting post and nice photos. Next summer we also would like to walk the butterfly canyon.
ReplyDeleteThank you. It is some years since I wrote about Red Butterfly Gorge but you can find the post here: http://cretenature.blogspot.gr/2014/02/red-butterfly-gorge.html
ReplyDelete