Agios Stefanos – The First Flower

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.

*********************************************************************

LINKS:

Share your nature thoughts, photos and comments on Naturalists (the facebook page that accompanies this blog)

Explore the region with the #CreteNature interactive Hiking and Nature Map

Cretan Flora

Flowers of Crete;

BIRDS OF CRETE

Crete Birding

Greek Butterflies and Moths

Aquaworld Aquarium

Visit Greece (National Government Tourist Office)

A Recipe For Life

We seem to have taken quite a detour last week to get down to this level and the waterfall should be over there somewhere. We’ll follow our ears and get there somehow but first, that looks interesting. There’s probably a correct technical term for these shallow erosions but I just call them cavelets. Let’s climb up and take a look. As you can see from the staining of the rock face, water is leaching minerals from the rocks and if you look up there you can see small stalactites forming. There are also white deposits blooming on the walls which my geologist friends tell me is probably gypsum/selenite.  They contain calcium and sulphur so, along with the limestone rocks which contain calcium and carbon, and the water, we have carbon, oxygen, and hydrogen (the basic elements of life) plus at least a couple of others to add to the recipe. We’ll push our way up through these bushes using this tumbling water course as our stairs and see what’s going on.

And up here, below the dripping stalactite, if you look carefully you can just see some threads of green algae forming. There’s a whole world of wonder in this little splash pool which began when large molecules of dissolved organic substances from the stalactite attached themselves to the wet rock. These neutralised the electrical charge of the water surface and allowed bacteria to colonise and they, in turn, secreted sticky strands that formed a nutrient trapping matrix. This matrix, known as the biofilm to periphytologists (people who study slimy rocks – yes, there really are such people), then served as a base for more bacteria to expand and diversify the biofilm and then for our green algae to grow. The algae, in its turn, will provide a home for microscopic life forms such as the ciliate we found in Life In The Olive Grove .

Algae are very basic life forms but we also have some higher forms of plant life up here. These fig branches, tenaciously clinging to the underside of this crack are just coming into bud and down in the damp crevices we have some lip ferns whilst out on the dry, stony ground, the beautiful but dangerous mandrakes are coming into flower. Their relative simplicity or complexity is reflected in their evolution: the flowering plants which include the fig and mandrake have been with us for about 120 million years, the ferns about 320 million years and the green algae maybe as long as 500 million years. Us? Well, as primates about 55 million years but as Homo sapiens only a couple of hundred thousand years.

Have you noticed these cottony threads in amongst the berries of this lentisc bush here? Alongside the evolution of plants came the evolution of insects and these threads look like the work of woolly aphids. Pass me the field microscope and I’ll see if I can find one for you. There’s one look, if you study him closely you can see him sucking up the sap from the plant. And where there are insects there are predators; there’s a minute spider that has his eye on stuffed aphid for lunch. Talking of which, let’s see if we can find some cave spiders lurking in the deeper recesses.

Do you think that you can wedge yourself up into that crack and see if there’s anyone about? Plenty of webs? That’s a good sign. You’ve found one? Good, I’ll squeeze in beside you and take a look. Hmm. It’s not a cave spider but he is rather interesting. Do you remember me telling you that you don’t have to worry about spiders in Crete because we only have one venomous one and you’re unlikely to come across it? Guess what? You’ve found one. Sorry, probably not the best time to impart that information when you’re perched precariously thirty metres up a cliff face, but don’t worry they’re pretty shy creatures and he won’t bother you unless you threaten him. All the same I think we’ll climb down. That was a Mediterranean Recluse Spider and although his bite can cause nasty skin lesions, a condition known as loxoscelism for which there’s no known treatment, it is rarely fatal. Having said that, there was a fatality last year in Italy but I believe that the unfortunate victim was already suffering from some sort of immune deficiency, which would have been a contributing factor.

Still, venomous spiders aside, a pleasant little diversion and a different angle from which to look at this wonderful thing called life. Now how are we going to get down from here?

The Extra Bit

Last week I glibly said that there is “only one authentic palm lined beach on the whole continent [of Europe]” and that was at Vai on the east coast of Crete. I am indebted to Jackie Strasis for reminding me that Phoenix theophrasti also lines Preveli Beach in southern Crete and I have also learnt that there are yet more at Ayios Nikitas in Heraklion Prefecture. Further research has turned up one other native European palm, The Mediterranean Dwarf palm, Chamaerops humilis, which lives in south west Europe. Just goes to show – you can’t believe a word that I say. Thanks for correcting me Jackie.

*********************************************************************************

LINKS:

Naturalists (the facebook page that accompanies this blog)

See detailed pictures at http://www.inaturalist.org/login  (search - people-stevedaniels-observations)

The Nature of Crete  (Flipboard Magazine)

Cretan Flora

Flowers of Crete;

BIRDS OF CRETE

Crete Birding

Greek Butterflies and Moths

Aquaworld Aquarium

Visit Greece (National Government Tourist Office)