The Problem With Icarus

A beautiful sunny start to 2018 and I wish you all a Happy New Year. The other day I passed the back of a curious concrete structure south of Lithines and I decided to stop and walk around to the front of it. Here it is, come on I'll show you. Once upon a time these hexagons were all mirrored which would have been a spectacular sight for that buzzard up there. Despite looking like something out of a Bond movie, it was actually an early solar power experiment. Crete is no stranger to discovering the power of the sun of course. Back in the day an engineer called Daedalus was imprisoned on Crete with his son Icarus by King Minos. In an ingenious escape plan Daedalus made wings of feathers and wax for the pair of them. Icarus flew too close to the sun, the wax melted and he fell back to earth with a splat. Actually both Icarus and the story crash at this point because the higher you fly, the colder it gets. Far from melting, the wax was more in danger of icing up. The result would have been the same of course.

Many animals shun the heat of the Cretan sun by hiding under rocks and with so many of these hexagons lying around in the undergrowth I reckon we can have a flipping good day finding some of them. Lets start with a couple of myriapods and dispel a few myths about legs. As children we were taught that centipedes had a hundred legs and millipedes a thousand (and their names reflect this). Neither fact is true. Myriapods, the group to which they belong means ten thousand legs and that's wrong also. Centipedes can have anywhere between 30 and about 350 legs (this one has about 40) and even the most leggy of millipedes only has 750. Our curled up friend here has about120. In addition to this they grow to adulthood by adding segments and legs as they develop, starting with as little as three segments and six legs, so counting legs is not a good way of differentiating the two animals. The trick is to look at the arrangement: centipedes have one pair of legs per body segment, millipedes have two.

I don't know if you've noticed but there's a door in the floor over there which can only mean one of two things. It's either a portal to another dimension or a flat-pack fridge (I often wonder what IKEA do with ideas that don't quite work). Let's open it up and find out what lies within. Corrugated cardboard which seems to be of interest to hundreds and hundreds of ants. I wonder what they find so fascinating? When reading about ants one often comes across the prefix 'myrm' (people who study ants are myrmecologists, seed dispersal by ants is called myrmecochory and so on) and the words come from the Greek 'myrmex'. There is an ancient Greek myth regarding Aeacus and Aegina who grew up alone on the island of Aegina. Getting rather bored of calling out “Aegina” and getting the response “Are you talking to me or the island?” (which wasn't a very good joke in the first place but pales considerably after the hundredth repetition) Aeacus asked Zeus to provide a bit of alternative company. Never one to do things by halves Zeus turned all the ants on the island into men and women and they were known as the Myrmidons who later fought with Achilles at Troy. There is an alternative version in which the Myrmidons were supposed to have been descended from the son of Zeus and Eurymedusa whom he seduced whilst appearing in the form of an ant but that seems somewhat impractical on many levels, even for Zeus.

Moving on to this Lentisc bush for a moment we seem to have something interesting going on. The spider is our old friend Cytophora, the Tropical Tent Web Spider, going about her business of cocooning food trapped in her web. But I'm rather more interested in this little bug that she seems to be ignoring. If I just extract it and turn it over in my hand... Yes, despite the faded colours which indicates that it may have been trapped for some time, it is definitely Zelus renardii. This Assassin Bug, you may recall, is a newcomer to Europe having been discovered on mainland Greece in 2011and here on Crete by ourselves in 2014 (see Red Autumn). Now the question is, why has she not parcelled it up for later consumption? We'll have to keep our eyes out for further instances and see if this is just a one-off or a more general occurrence.

Whilst we're on the subject of dead insects I've just spotted a deceased grasshopper on the floor here. This is one of at least three types of bandwing grasshoppers with reddish wings on Crete which you normally see as just a flash of red, like a miniature firework exploding beneath your feet, as you walk through dry scrubland like this. It is only when they have passed on that you can get a chance to open up their wings and admire their exquisite tracery. The patterning also helps to identify the species. This one is the Slender Digging Grasshopper, Acrotylus patruelis.

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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)

Old School Spiders and Killer Spuds

We'll start where we left off last week at the derelict dwellings and make our way down to the heart of the village but before we do I've just seen something large and red fly by my nose and land on that wild carrot over there. What a magnificent specimen (and go compare that for a facial appendage). Those fantastically large antennae mark him out as one of the Longhorn Beetles (family Cerambycidae). The antennae are used primarily for smelling the air but in some insects they actually help to stabilize their flight (which is a bit counter-intuitive as you'd think that they would make the creature a bit of an awkward flier). But when you think of a tightrope walker with a long balancing pole it makes a bit more sense.

This is something I wasn't expecting to find, a terrace full of potatoes planted on the hillside totally out of context with everything around it. The flowers are rather pretty and very similar to Silver-leaved Nightshade. The reason for this is that they are both in the same family (Solanaceae) and like all members of the Nightshade family they contain the poison solanine as a natural insecticide. Potato poisoning is rare but not unknown: in 1979 a group of 78 schoolboys from south London were poisoned and although they survived to tell the tale (previous cases have been fatal) they were pretty ill and some were confused and hallucinating for several days afterwards. My grandmother's old maxim: 'never eat green potatoes' turns out to be good advice. Although the green is merely chlorophyll found in all green plants (for which reason I'd always rather discounted my grandmother's warning) it is an indicator of the build-up of solanine. Ah, the old 'uns knew a thing or two. Generally the amounts of solanine in spuds (and tomatoes and aubergines too for that matter who are also in the same family) is too low to cause any problems at all.

This is what passes for Central Drive in Ferma and I see that a colony of ants are using those black water pipes as a motorway. They seem to be moving house judging by the number of eggs and pupae being transported down the hill. We always think of bees and wasps as being natural compatriots but ants fall into the same group of insects too; the Hymenoptera. How they are related within the group has always been a bit of a puzzle as it all depends upon which aspects of their anatomy and/or behaviour you use as your yardstick. Anyhow, a few years back a group of scientists led by Bryan Davis in California decided to solve the puzzle once and for all by scouring the countryside for ants, wasps and bees of all denominations and taking DNA samples (I'm not sure that I'd have volunteered to be a part of that team). They sequenced the genomes and found that the majority of wasps went their own way from a common ancestor at an early stage. A few, the scolid wasps and allies, along with the bees and ants decided upon a different evolutionary path. The bees and ants then parted with the scolids and finally the bees and ants separated. All except the thread-waisted wasps which followed the bees' evolutionary path (so maybe we should call them thread-waisted bees?). So, when did we learn that ants are more closely related to bees than wasps are? Not until 2013 which just goes to show how much there is still to be discovered about the natural world. [1]

Oh look, a red spotted dandelion. Ye gods! The spots are alive. The area is literally crawling with little red animals. A quick leg count under the hand lens – eight so they're arachnids. They are a type of mite going by the name of Balaustium. There are a couple of clues to identifying this genus: firstly, unlike other members of the Erythraeidae family they are pollen feeders rather than predators and secondly they have a noticeable gap between the second and third legs. Apparently, although they are vegetarian they can give you a nip so maybe it's not a good idea to let them swarm up your left leg like that.

I see that you've gone for the squishing method of mite removal rather than the gentle brush. Maybe not so wise, your leg now looks like a war zone. No matter, come and have a look at this harrow I've just stumbled upon. Is this the original Harrow-on-the-Hill? I wouldn't have thought that this is the most useful piece of equipment you could have on a steep hillside like this but it explains how the potatoes got planted. There's another one of our jumping spiders down there look. There is a controversial theory that these spiders are socially superior to other spiders and this would appear to be supporting evidence for that theory. How so? He's obviously an Old Harrovian. He's even in the school colours.

The Extra Bit

[1]  Phylogenomics Resolves Evolutionary Relationships among Ants, Bees, and Wasps from Current Biology Volume 23, Issue 20, p2058–2062, 21 October 2013

I suppose I ought to tell you a bit about the village facilities in case you fancy a visit: plenty of places to stay including a hotel (Porto Belassario) and a number of self-catering apartments. There is also a campsite at nearby Koutsounari. A choice of places to eat and drink as well as a village store, a butcher, a baker (no candlestick maker), two hairdressers and a petrol station. And me of course. Everything you need really. Yes, we have no MacDonald's, KFC, faux Irish Pubs, rowdy nightclubs or strip joints(but we do have bananas in season).

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LINKS:

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

See detailed pictures on Flickr

Read more about the flora and flora of the island in The Nature of Crete (Flipboard Magazine)

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)

Worlds Within Worlds

Do you want the good news or the bad news? The good news is that we’ve made it safely through the Milonas Gorge. The bad news is that we have a flipping great waterfall ahead of us which means we’ll have to find a way around and down and there are no paths to follow.

No matter, the sun is shining and there’s a flying circus in the sky. In case that seems a bit odd, forget the tents, clowns and performing seals and think of the origin of the word. Circus comes from the Greek kirkos meaning a circle or ring and was applied to a place of entertainment where the seats were arranged in a circle around the performing area. It is also the generic name of the birds that circle as they hunt which we know as Harriers. There have been four species recorded on Crete: the Marsh; Hen (or Northern); Pallid; and Montagu’s. The last three are rare and the Marsh, although a frequent passage migrant in the spring, only overwinters here in small numbers. It’s a bit too high to make out details but it’s still an exciting start to the day as it’s the first Harrier of any type that I’ve seen in these parts.

This really is an impressive bit of landscape with the lower valley stretched out before us and the great towering limestone cliffs at our backs. Hard to imagine that this was once a sea bed. Look up to that patch of blue sky and try to visualise yourself looking up to the surface of the ocean instead. That it may also once have been a tropical beach is easier to imagine because the evidence is here at our feet. The thing about limestone is that it is good at preserving fossils and we’ve got a smashing fossilized palm fan here. Pity it’s too heavy to lift, it would have looked nice by my fireside at home. Palm trees aren’t entirely tropical, there is one species (Phoenix theophrastii) that is native to Europe but there is only one authentic palm lined beach on the whole continent. Where? Crete of course, at a little place called Vai on the east coast. Remind me to take you there some time.

The water here is pushing its way around the rocks, trying to get to the head of the waterfall, which means that there are some intriguing little pools around. Let’s get a sample under the field microscope and see if there’s anyone at home. That little patch of algae clinging to the rock looks promising. Ooh look, an aquatic worm. There are three types of worm that you can find in pools like these. There are nematodes which thrash about frantically (you may remember that we found some three years ago down at Ferma rock pools – see Rockin' All Over The Shore); flatworms which glide around rather gracefully; and oligochaetes like this one which are rather squirmy wormies related to the common earthworm.

We seem to be making our way steadily downwards with loads of lichens, masses of mosses and cascades of chasmophytes (rock loving plants) lining our route but I see that we also have some lovely little yellow fungi down near our feet. Do you see that milky droplet exuding from the stem?  It looks like latex (but not the same latex that you find in plants) which is exuded by members of the milk cap family. However they exude latex from outside the mushroom not from the stem and there are no milk caps with this colour and habit so it’s a waxy cap like the ones we found in the gorge last week. Just when you thought fungi couldn’t get more confusing!

Hello, we’re into the jungle. It looks as though we’ll have to crawl through this bit. Still, while we’re down here we may as well have a look about and see what’s going on. How delightful, an ants’ nest, just what we need when we’re crawling along on our stomachs. But what’s this in the nest with them? You see the little orange insect trying to hide? It’s an Ant-loving Cricket (Myrmecophilus). Ants’ nests aren’t just for ants. They are like big cities and, just as with our cities, they have a diverse wildlife all of their own. Hundreds of different species have adapted to ant city life and this is just one of them. Absolutely tiny for a cricket, they never grow wings because they never leave the city, they’re deaf and mute and have very poor eyesight. They don’t have sex either, the females have virgin births, a process known as parthenogenesis. Doesn’t sound like much of a life but they seem to get by.

The Extra Bit

At last we’ve emerged into the open and even though we’re approaching midwinter a few of the flowers are beginning to emerge. We’ve got anemones, fumana, Cretan cistus and field marigolds all beginning to open their petals in the midwinter sun. If you look over there you can see the waterfall and that’s the direction in which we’ll be heading next week.

Thanks to JJ Wuilbaut at  Mediterranean Fungi for educating me on the difference between Waxy Caps and Milk Caps and to various members of Crete Birding for chatting about the various Harriers on Crete.

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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)

Communication

How fish school

During last week’s snorkel around this beautiful little lagoon did you happen to notice all the little fish swimming around near the surface? Ever wondered how they all manage to change direction at the same time? Yes, you can put your towel down and sunbathe now but just take a closer look at this couple of little fellows I’ve just netted. Pretty aren’t they? That dark line going from stem to stern is called the lateral line and it’s packed full of hair cells which can detect minute movements and vibrations in the water. These signals are then sent electronically to the brain giving the fish an extremely accurate picture of its environment even in dark and cloudy waters. They can locate prey, avoid predators and, of course, all turn together in a way that would make any synchronised swimming team give up and take an early shower.

Cardinal Butterfly

This is just one of the methods that animals and plants use to communicate with each other and while we’re sitting here enjoying the sun I thought we’d look at some of the other ways they do it. That stunning Cardinal Butterfly that’s just landed behind us for example. Easily recognisable by the way, from the greenish sheen to its hairs.  Bright coloured butterflies semaphore their colours to each other and even the comparatively plain female Cabbage White gives a brief flash of ultraviolet light on each downstroke of her wings when she’s ready for a mate. So, butterflies too have their flashers, not just the girls after a night out in the bars of Malia.

Blackbird

Birds, as we know, sing beautiful songs, particularly the males when they want to attract a mate but even that is not as simple as it seems. During the reproductive season the blackbird, famous for his ability to improvise and embellish his repertoire, actually sings a simplified, functional version of his song proclaiming ‘here I am’, ‘this is my territory’ ‘ready when you are’. All those twiddly bits and sound incorporations (I knew one once who managed to include a police siren into his song) come later when he has time to relax and experiment.

Now, if you could just move your towel a bit – no, it’s not in my way as such, it’s just that you’ve parked it on an ants’ nest that I wanted to talk about. You didn’t need to move it that far away – or quite so quickly. You’ve disturbed the ants now but still, you’ve created masses of communication in the nest. 

Ants have a sophisticated communications network

Ants are what are known as eusocial insects (which is like social but to a very high degree), living and working almost like a single entity. To get this level of coordination you need a pretty sophisticated communications network and the key to this is pheromones, chemical substances that can be detected by other ants through various sense organs such as their antennae.  Female moths use pheromones as well to attract males over long distances and so do we to a certain extent (ever wondered why you were inexplicably attracted to someone? Pheromones at work). But back to theses ants; as well as chemoreception (the technical term for communicating with pheromones) they are very touchy-feely creatures, passing information by stroking each other with their legs and antennae and they are also surprisingly vocal. We can’t hear them of course but they stridulate like crickets – that is, they rub parts of their bodies together, and produce high pitched chirps. Tree dwelling ants go one better, they also send vibration messages back to the nest by drumming their heads against the wood (the insect world not only has flashers but head bangers as well so when we say that certain disruptive elements in our society are “behaving like animals” maybe we should be more specific and say “behaving like insects.”). So what looks like a mass of confusion down there is a highly complex hub of smells, vibrations and sounds ensuring that every ant knows what it should be doing, and where and when it should be doing it. Amazing little animals, ants. Have you got them all off of your towel yet?

Mallow

But what about plants? The idea of plant communication was ridiculed for years (as in the old song parody: “I talk to the trees, [that’s why they put me away]”) but we are now investigating myriad ways in which plants pass messages to each other. I spotted a little drama unfolding amongst the mallows on our way down here so if you pack up your towel and sun-tan lotion I’ll show you on our way back.

Ant and Aphids ona Mallow leaf

Down here on the leaves we have some newly emerged green aphids and an ant. The aphids want to eat the plant and as they do so they will excrete a sugar rich substance called honeydew. This is what the ant is after. The plant doesn’t want to be eaten so it will mount a chemical defence and produce toxins to deter the aphids. It doesn’t necessarily stop there as we now know that some (maybe all) plants produce pheromones which shout the equivalent of  “APHIDS - INCOMING!” to  their neighbours who can then mount their own defences prior to an attack. The question that arises in my mind is – how does the ant just happen to be there as the aphids emerge? Could be he just stumbled across them but we know that the ants’ main method of communication is based upon pheromone chemoreception so, has the ant picked up the “APHIDS - INCOMING!” transmission? Military intelligence in action as it were. This would be counter productive to the Mallow as the ants will shepherd and protect the aphids from predators such as ladybirds. It’s possible that the plants are aware of the ants’ abilities and send out a scrambled pheromone message that the ants can’t decipher and this one did indeed just get lucky. Or maybe the ant has learnt to decipher the code? As always when we start looking at nature in action there are far more questions than answers.

                                                

Until next week – happy hunting and, as Sherlock Holmes would say: the trick is not just to look but to observe.

As always you can see all the pictures including insets in detail on Flickr

Add your own comments and observations by using the comments button at the foot of the page or find out more about Crete nature by following the links below.

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LINKS:

Naturalists (the facebook page that accompanies this blog)

Flowers of Crete;

BIRDS OF CRETE

Crete Birding

Greek Butterflies and Moths

Aquaworld Aquarium

Visit Greece (National Government Tourist Office)