Italian Wall Lizards and Rapid Evolution

The last few years have been busy but have brought with them an opportunity to travel and to learn about new places, but little time to write.  Each year I spend a bit of time in Europe and extend my work trips to include a bit of time off.  Usually these trips are centered on Germany but I try to visit a few more places and in 2015 I had the opportunity to spent a few weeks in northern and central Italy.

A number of things caught my attention, for example how Virginia Creeper (Parthenocissus quinquefolia) has become invasive in much of Europe but especially in northern Italy, how different the color pattern of the Hooded Crow (Corvus cornix) is to what I’m used to seeing in the Americas or Asia, the deep similarity of vegetation assemblages and species to those in North America occupying similar habitats, and, of course, the fantastic views and towns perched on hills or nestled into narrow canyons, like Riomaggiore.

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Riomaggiore, one of the Cinque Terre, in La Spezia

Of the things I saw in Italy there is one I’d like to focus on for this post.  It is a small, common lizard, often overlooked.

The Cinque Terre coast is very similar to parts of the California coastal chaparral and dry coastal forests, so it was no surprise to find lizards sunning themselves on the trails, hiding in the stone walls of the terraced vineyards, and rustling through the oak, laurel, and chestnut leaf duff layer.  Lizards are funny beasts, sometimes bold as you please standing on their rocks as though they own the world, other times bolting at the bend of a blade of grass.  Unfortunately, these lizards were wary and fled my approach, leaving me with only vague, scaly impressions of what they looked like.

It was in Florence where I finally saw one of the little fellows clearly.  I’d had enough of the noise and crowds and escaped to the Boboli Gardens, where I paid a bit more attention to the plants than I did to the impressive array of statuary.  Near a hedge a slight twitch amongst the dried leaves caught my eye and revealed itself to be a beautiful small green lizard with black and tan patterning sunning itself on a bed of withered sycamore leaves.  It was almost done shedding its skin and the colors were vivid.

Florence Italian Wall Lizard (Podarcis sicula) 112.jpg

Italian Wall Lizard (Podarcis sicula subsp. ?) in the Boboli Gardens, Florence

This is, of course, the Italian Wall Lizard (Podarcis sicula), a highly adaptable small lizard native to Italy and nearby regions.  This not an endangered or even rare species, on the contrary, it is quite common within its range, and its adaptability has led to the development of at least 62 recognized subspecies.  I did not know any of this when I first encountered the species, but something about it seemed familiar.  It wasn’t until I came across several more of them in Bracciano and had the time to identify them that the niggling sense of familiarity clicked.

In 1971 scientists transplanted 10 individuals of this species (5 breeding pairs) from the island of Pod Kopište to Pod Mrčaru, Croatia, a small island; only a few hundred meters long on its longest axis; with a resident population of a different lizard species, the Dalmatian Wall Lizard (Podarcis melisellensis) .  The goal of this experiment was to test competitive exclusion in island biogeography theory.

Pod Mrčaru map.jpg

Unfortunately the 1970s were a troubled time for that part of Europe and Yugoslavia began its fragmentation into what are now Slovenia, Croatia, Bosnia/Herzegovina, Serbia, Montenegro, Kosovo, and Macedonia.  Trouble mounted through the 1970s and in 1980 Josip Broz Tito died, opening up a power vacuum exacerbated by ongoing ethnic conflicts.  It wasn’t until the mid-1990s that the dust more-or-less settled.

The long lasting conflicts in the region put a halt to the experiments of Eviatar Nevo  and his team on  Pod Kopište and Pod Mrčaru.  The lizards, of course, were undisturbed by the commotion of the excitable bipeds and the tiny island was left undisturbed until about 2004 when tourism was allowed in the area. Researchers returned to the island shortly afterward.

To the researcher’s surprise, they found that the initial 10 introduced Italian Wall Lizards had increased to a population of over 5,000 and that the native Dalmatian Wall Lizard was now locally extinct.

Further investigation revealed the real shocker; in the brief time the island had been left alone, some 30 lizard generations (abut 36 years), the introduced Italian Wall Lizards lizards had undergone profound evolutionary changes.

This is what had been tickling the back of my mind when I saw that first lizard in the garden of Florence.  Long before my trip to Italy I had seen a documentary discussing the rapid and unexpected changes these lizards had undergone.  I must have remembered the morphology of the lizard, but had lost the connection of that particular lizard to the documentary.  I can’t find the original video I saw, but there is a Richard Dawkins video on the subject:

Italian Wall Lizards are primarily insectivores, but in their new habitat they changed to become primarily herbivores.  For a omnivore like us this doesn’t seem to be a startling thing, we regularly shift back and forth between different types of foods, sometimes craving meat, other times preferring vegetables and many people make long-term dietary commitments to avoiding animal products entirely while other cultures have traditionally had a diet consisting almost entirely of animal products.  We are large animals and have evolved to be generalist gourmands.

For the lizards this switch is not so simple.  Plant matter needs time to ferment and break down to make digestion possible.  Plant matter can be extremely tough, requiring more effort to consume.  The shift from eating insects to eating plants is akin to shifting from eating exclusively fast food to eating primarily home-cooked meals.  Before you just ate what you bought, but now you need a working kitchen and utensils for preparing and cooking the food.

The introduced lizards developed a host of traits to aid in the consumption of tough plant matter; cecal valves (muscles that separate the large and small intestine, slowing down food digestion and effectively creating fermentation chambers – a bit like ruminates with their multiple stomach compartments-, allowed them to process the tough plant cellulose), larger, stronger jaws and bigger muscles to assist in the harvesting plant matter, changes in head morphology, and an over-all larger body size.

These changes may not seem like much, but they’ve been likened to humans evolving a new appendix in only a few hundred years.

Interestingly, the changes in food supply also changed the social behavior of the Italian Wall Lizards, leading them to be less territorial.

Changes in general should not come as a surprise considering the variability of Podarcis sicula.  After all there are some 62 subspecies of this lizard.  Even the between the individuals I saw in Florence and Bracciano there appear to be differences in head shape, color, and patterning.

Wall Lizard comparison (Podarcis sicula) Bracciano 173 Florence 115 small.jpg

Comparison between Italian Wall Lizards (Podarcis sicula) in Florence and Bracciano

What is surprising is how rapidly major evolutionary changes took place.  We tend to view evolution as a gradual process taking place over millennia with changes taking place so gradually that they are almost unnoticeable in human relevant timescales.  We know this is not true, but this view is so prevalent that it forms the backbone for one of the common critiques of evolution by those so inclined. Here we have a lovely example of evolution in action on a human relevant timescale. Better yet, it is an unexpected change, one that could well lead to a new species developing, if given enough time.

This is the largest change seen in this species, but it is far from the only case.  Italian Wall Lizards have been introduced in Turkey, Spain, and the US.  One of their populations in the US in New York, where they were introduced in 1966 or ’67 (most likely via the pet trade) has revealed an interesting an unexpected adaptation.  In the home range of the Italian Wall Lizard the temperatures rarely drop below about -7C and do not remain cold for prolonged periods.  As a result the lizards are active throughout the year with only brief periods of inactivity.  In New York, however, temperatures can drop to -20C and remain below freezing for extended periods.  It turns out that these robust little reptiles have a hidden ability and can supercool themselves and hibernate through the colder months in New York, a behavior not seen in their native range.

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Italian Wall Lizard (Podarcis sicula) in Bracciano outside the Italian Air Force Museum

It is easy to overlook the little things and to take the common things for granted, but it is often those very things that open our eyes and our minds to greater understanding of the world around us.

These humble little lizards provide a window into evolution and adaptability, a window that might never have been noticed if not for the happenstance of a lost experiment carried out decades prior.

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Tides, Why Tide Charts Don’t Average to Zero, and Agendas

Tides are an important part of life on earth. Earthly tides are primarily governed by the moon, a result of Lunar gravity tugging on the planet as the Earth spins along side of our over-sized neighbor.

A few days after the 2013 "supermoon"

A few days after the 2013 “supermoon”

Tides affect both the earth’s crust (raising it enough so that large particle accelerators must be designed with the geo-tide in mind) and, more familiarly, the oceans. Technically speaking, all bodies of water are affected by the tides, but the large tides experienced by coastal dwellers is a result not only of the Earth-Moon-Sun gravitational dynamic but of resonance, coastline shape, and of characteristics of the ocean floor.

Resonance is simply the self-reinforcing effect of synchronization. The most familiar form of resonance for most people may be pumping your legs on a swing. If your timing is right the small amount of energy added to the pendulum motion by pumping your legs will lift you higher and higher. If your timing is off you can kill your speed and come to a stop. You can do the same with your hand and a basin of water, a small amount of hand motion will quickly wind up sloshing water out of a bathtub. Swings, tides, and lasers work on this principle of resonance.

The shape of the coastline and the depth of the ocean floor can concentrate or diffuse tides as well, focusing or dispersing the vast energies at play. This is why the tides in places with fjords like British Columbia and Norway can be so dangerous.

I grew up near the ocean and spent a lot of time watching the ocean and exploring tidepools and the rocky beaches of the California coast.

Mussels anchored on exposed rocks in the intertidal zone.

Mussels anchored on exposed rocks in the intertidal zone.

The interesting part of the coast was not the sandy beaches, but the craggy high surface areas that trapped pools of water. All sorts of creatures live in these pools. Strange and wonderful creatures like the Gumboot Chiton, Cryptochiton stelleri, large molluscs that crawl out of the water at low tide to feed on exposed seaweed.

Cryptochiton stelleri, or Stellars's Hidden Chiton, so named because the characteristic eight bony plates are hidden under rugose red skin

Cryptochiton stelleri, or Stellars’s Hidden Chiton, so named because the characteristic eight bony plates are hidden under rugose red skin

In tidepools I have found and caught octopus, eels, and fish, but two of the most common residents are Shore Crabs

Shore Crab, a common California coast resident

Shore Crab missing an arm, a common California coast resident

and anemones, both hovering between the scavenger and hunter niches.

Anemones: close-up of arms

Anemone: close-up of arms

These and many other creatures live in what is known as the intertidal zone, the region of the coast that is above low tide and below high tide. This is an area of tremendous free energy. Energy is a two edged sword as any scientist or engineer can attest to. Energy makes all things possible, and most things can be broken down into either growth or destruction. Creatures that live in the intertidal zone reap the benefit of straddling two environments, feasting on the windfall of both, but the fierce waves and tides also expose them to the dangers of being left to suffocate in water, desiccate in the sun, be torn from holdfasts, and fall prey to other adaptable creatures. Excellent potential for great growth or swift destruction.

In the intertidal zone there are bands of life that roughly conform to the amount of time spent out of water. Mussels and barnacles occupy the upper reaches and are the most familiar.

Mussels and Gooseneck Barnacles on exposed rocks.  Both are tasty to eat.  Mussels are commonly eaten in the US and Gooseneck Barnacles fetch high prices in Spain, where people risk their lives to collect them.

Mussels and Gooseneck Barnacles on exposed rocks. Both are tasty to eat. Mussels are commonly eaten in the US and Gooseneck Barnacles fetch high prices in Spain, where people risk their lives to collect them.

Lower down, in some places, Sea Palm grows in dense stands, often damaged by the waves.

Sea Palm (Postelsia palmaeformis), the only species of this kelp and one of the few that can live for extended times out of water

Sea Palm (Postelsia palmaeformis), the only species of this kelp and one of the few that can live for extended times out of water

At each level a different selection of species dominates creating a many-layered composite of ecotones, much like a mountain in miniature. The vertical ranges for these species collections is so narrow that it can be used to track sea level changes.

If you want to see nudibranchs, octopus, and sandcastle worm, then when do you go to the coast?

sandcastle worm (Phragmatopoma californica) colony

Sandcastle Worm (Phragmatopoma californica) colony

Clearly you go at low tide… but what does this mean?

One of the things that bothered me about tide-charts (like the one below) is that if you average the high and low tides you do not get zero.

Graphical tide chart made with the TideTrac app

Graphical tide chart made with the TideTrac app

I went out a while back to experiment with day-time long exposure photos. This is the tide chart for the day. Notice that the lowest tide of the day is still +0.4 feet (12cm)? The average tide for the day is +2.9 feet, nearly a meter. What is that all about?

The answer is that tide charts were designed for sailors, not tide-poolers or surfers. Tide charts are set by a datum, one of 17 potential datums, that all are based off of the LOWEST tides, not the average tide. For a sailor who wants his boat to stay in the water and not be slammed against rocks, this is important.

Even a small bump carries a lot of energy

Even a small bump carries a lot of energy

For the rest of us, it is a little non-intuitive. We have picked the lowest tide as the datum because that is what was important to the people making the charts at the time. If it had been house contractors instead, the datum would have been the highest tides. Tide-poolers would probably have picked the average tide as the datum, making it easy to determine when the most species would be exposed at any given moment.

There is a lesson here; be wary of maps and charts. Maps and charts are made to tell a specific story, a story with a perspective, a message, and an agenda. Like an advertisement on TV or a political speech, it is important to be aware of both the audience and the proponents of the product. And in truth, there is little that is more political than maps and charts.

Oh, the long exposure photos turned out great.

Ten seconds of waves washing in and out during the day

Ten seconds of waves washing in and out during the day

***

Note: for those of you who look at the full-sized photos, several of these have been pulled from my archives and were taken with my first digital camera; a Canon ELPH from the early 2000s. A great little camera, but of a disappointingly low resolution.

Things that Gall – plants and parasites

The word “galling” is particularly evocative.  In its most simple form something that galls is merely annoying or vexing, but the true definition connotes annoyance taken to an extreme level.  The sort of thing that will do you no harm but rankles tremendously; much like being forced to pay taxes to support actions you object to.

For us these annoyances are mental and emotional, for plants these galls are physical but are often merely annoyances for them as well.

Dried oak apple gall  on Scrub oak in California

Dried oak apple gall on Scrub oak in California

Many plants suffer from galls and the galls are so singular in form that they can be reliably used to identify individual parasite species.  A fantastic book on identifying plant galls for the California region is the Field Guide to Plant Galls of California and Other Western States.

Oak trees seem to be particularly susceptible to parasites of all sorts and a common manifestation is the Oak Apple Gall, most often seen as a hard, woody ball dangling from a twig.  These galls are created by the Oak Apple Gall Wasp, a common name for a variety of small wasps that inject their eggs into the midrib of a developing leaf and chemically trick the tree into growing a protective shell for the developing larvae.  Despite appearing woody when dried, this type of gall is actually a modified leaf.  The delicacy of these galls is more easily seen when they are still green.

Fresh Oak Apple Gall - Virginia

Fresh Oak Apple Gall – Virginia

The developing wasps browse on the oak tissue and are often preyed upon or parasitized by other animals, including birds, raccoons, and a whole host of insects, other wasps included.  Some insects use the gall for their own protection, sharing the space with the wasp larvae.

Oak Apple Gall with non-wasp larva inside next to a Twig Gall - California

Oak Apple Gall with non-wasp larva inside next to a Twig Gall – California

Certain Oak Apple Galls, the Iron Galls,  in Europe were collected to make ink.  For 1500 years ink make from the iron gall was the primary source of writing quality ink in the Western Hemisphere.  For anyone interested Evan Lindquest provides detailed instructions on how to make your own iron gall ink.

Like may things we have a long history with there is a great body of mythology and folk-lore that has accumulated around these galls.

Many galls are hard and woody, there is a Twig Gall I sliced in half in the photo above.  It appears to be empty, but a dark brown patch filled with frass (insect excrement) can be seen winding its way though the bloated tissue.

Oak Apple Galls often fall from the tree, but Twig Galls are a more permanent fixture of the tree.

Twig Gall on a scrub oak branch flowering from the tip - California

Twig Gall on a scrub oak branch flowering from the tip – California

Right now the Scrub Oak is blooming along the coastal mountains in Southern California.  The twig galls are uniformly clustered near the tips of the branches, with many of them crowned by small clusters of flowers.  This provides a bit of insight into the formation of these and other galls.

The gall must be grown, and while the living plant cells are constantly dividing, the true growth of a woody plant takes place at the tips of the branches and roots, or at the apical meristem of each limb.  The cells in the apical meristem are undifferentiated,having the potential to become a wide variety of plant organs, much like stem cells in animals.  The parasite, be it a wasp, bacteria, or virus, co-opts these “stem” cells and gives them new instructions.  In a way the galls are akin to a tightly controlled cancer initiated by the parasite organism.

The Twig Galls I was looking at today were insect formed and, as such, the insect needs to escape the protective structure once it is mature.  Many of the galls had little holes in them showing where the little wasps has crawled out.

Exit holes in a Twig Gall - California

Exit holes in a Twig Gall – California

The variation in galls is astounding.  I have seen leaf galls on wild roses that look like tiny sea-urchins dipped in vermillion.  There are galls that not only force the plant to grow a protective structure around it, but that trick the plant into producing nectar to attract ants which in turn protect the growing larvae from predators.  Many are extremely colorful and the shapes are widely varied.

Colorful leaf galls on a Sugar Maple leaf - Vermont

Colorful leaf galls on a Sugar Maple leaf – Vermont

The common theme is that the galls are all formed in developing tissue, leaves, new twigs, flowers, roots, or fruit.

A gall on Shadbush fruit - Vermont

A gall on Shadbush fruit – Vermont

Some of the Ichneumonidae wasps that make so many of the galls we see have developed a biological metallurgy, evolving zinc and manganese coated ovipositors which they use to inject chemicals and hormones into the plants they co-opt.

The specificity and regularity of the galls and the relationships between the plants and the gall formers speaks to a lengthy and complicated evolutionary history.

We pride ourselves (or are horrified by) our newly found ability to genetically manipulate plants and animals.  In truth, we have a long way to go before we catch up to what we often mistakenly call the “humble” insects.

A Long Flight over the Canadian Shield

Recently I flew from Istanbul to Los Angeles, following a great-circle route over Ukraine, Norway, Greenland, and Northern Canada.  As I always do when flying, I got a window seat and spent most of the flight peering out the window, developing a crick in my neck that took several days to loosen.

Much of the European and Greenland portions of the flight were shrouded in clouds, leaving me watching a vast expanse of what looked like glowing cotton.  Occasionally patches would open in the clouds and I would catch a brief glimpse of the land or sea below, and a look at one of the most talked about ecosystems on our planet.

Ice floes on the Arctic Ocean

Ice floes on the Arctic Ocean

The northern polar region, the Arctic.  This is a vast region centered on the bath-tub-like basin of the Arctic Ocean.  Discussing directions in the polar regions is tricky, for in the arctic, pretty much every direction that is not north is south, thus geography is a better indication of location than compass points.  On one side the entryway to the Arctic Ocean is narrow, shallow, and flows over the ancient land-bridge that once connected North America and Asia.  On the other side warm water flows up the Atlantic Ocean to the east of Greenland, keeping Europe warm and pushing the ice away from the Norwegian coast.  This is the primary point of water-flow into the Arctic Ocean.

To the west of Greenland a network of channels in the Queen Elizabeth Islands lets water slowly filter out of the basin, trickling back into the Atlantic via the southern opening of Baffin Bay.  Amongst the islands fierce currents keep polynyas open in the ice, providing open water for eider ducks and other sea-birds that over-winter in the Arctic.  Generally the whales will leave the Arctic during winter, but sometimes they become trapped and these polynyas provide the only places they can find air to breath.

Since we have been keeping records the sea ice extent has been getting smaller and smaller.  Records of sea ice extent and other cold-weather data can be found free of charge at the National Snow and Ice Data Center.

Several years ago, as part of a graduate project on Ringed Seals I looked at the changes in ice extent for the month of April over the last 30 years.  The photo of the broken sea ice above was taken on the eastern side of Greenland, a place where the sea-ice is extremely variable.

1981 - 2010 April Sea Ice Extent:  Darker colors indicate a greater number of years of coverage, lighter colors, fewer years of coverage

1981 – 2010 April Sea Ice Extent: Darker colors indicate a greater number of years of coverage, lighter colors, fewer years of coverage – green indicates areas outside of ice-cover that are shallow enough to provide foraging areas for Ringed Seals

The little flashes of ice I got to see through the grubby Turkish Airlines plane window were tantalizing, but they were only teases.  The interesting views were to come later, as we passed over the Canadian Shield.

Flying over over the Melville Peninsula, looking east to Foxe Basin... I think

Flying over over the Melville Peninsula, looking east to Foxe Basin… I think

Here, over the Canadian Shield, a 3 million square mile (8 million square kilometer) expanse of heavily weathered, exposed bedrock billions of years old the signs of past glaciation are evident.  Not merely evident, the fossil tracks of vast continental glaciers shout their presence to the sky.  Fortunately, I happened to be in the sky, with a camera at the ready.

There is a common misconception about glaciers.  People have heard that glaciers carve channels into the bedrock and grind down mountains.  This is only partially true.  Ice is not very hard, by itself ice can carve channels into rock the hardness of chalk or talc, but not into tough rocks like granite, the rock much of the Canadian Shield is composed of.  Ice levers out whole boulders and picks up loose material where it lies.  These become embedded in the ice and these are what does the scouring and carving.  The ice provides the weight and movement, much like a person provides the force when sanding or filing a piece of wood or metal, but it is the sandpaper or the file that does the actual cutting.

Ice, when it comes in glacier quantities, is an elasto-plastic material.  The upper surfaces are brittle and crack, making crevasses and seracs, but the deeper ice, down below the 50 meter mark, is more akin to a slow, cold silly-putty than to the brittle thing we put in lemonade.  When the ice is kilometers deep it oozes, flowing like spilled molasses over the land, dragging with it the entrained materials, grinding down high points, smoothing jagged surfaces, and hollowing out U-shaped valleys, leaving behind a stream-lined surface replete with the marks of its passage.

Rocky Mountain Trench in the Canadian Rockies - a classic glacially carved valley

Rocky Mountain Trench in the Canadian Rockies – a classic glacially carved valley

In both photos above the U-shaped valleys are clear.  These valleys come in all sizes, some more impressive than others.  The Rocky Mountain Trench in British Columbia is one of the more impressive ones, as is the Gilkey Trench in South-East Alaska.

The Gilkey Trench, the speck in the foreground is a person and each of the ripples in the bottom is 10 meters high

The Gilkey Trench, the speck in the foreground is a person and each of the ripples in the bottom is 10 meters high

These valleys are often found in mountains, places where the glaciers ground out material between the peaks, but left the high places alone.

Billions of years ago the Canadian Shield used to be home to vast mountains, now they are all gone, only their roots remain.  Erosion from various sources and repeated glaciations have scoured the Canadian Shield over and over again, grinding even the great mountains into low mounds, leaving traces that are best seen from the air.

Exposed bedrock showing fault-lines and ancient mountain cores

Exposed bedrock showing fault-lines and ancient mountain cores

The long, straight lines are old fault lines, places where geologic stresses broke the rock and let it slide against itself.  Here the rock is already damaged and the glaciers excavated long channels that look like canals from the air.  The distorted oval in the lower middle of the photo is where a bubble of rock forced its way up in the distant past, creating a mountain or large hill.  Now it has been ground flat and shows up in the surface pattern, much like cut wood shows the pattern of knots and grain despite being smooth to the touch.

Over much of the Canadian Shield soils are shallow to non-existent.  Even south of the tree-line vast areas are sparsely vegetated for lack of soil.  Roads are difficult to make as the land is smooth only at large scale and it is riddled with lakes and rivers.

In the winter the smoothest parts of the Canadian Shield are the lakes themselves and they are where temporary roads are made.

A road on the frozen lakes to the north of Yellowknife

A road on the frozen lakes to the north of Yellowknife

The last major glaciation was relatively recent, only about 20,000 years ago and the land is still recovering from the effects.  The whole Canadian Shield is undergoing isostatic rebound; with the weight of the up to 3 miles (almost 5 kilometers) of ice coming off the Earth’s crust it is now rising, seeking a new equilibrium as it floats on the liquid rock mantle deep beneath the surface.  Rivers and lakes are draining, the courses sometimes shifting as the land rises, carving out new pathways.  Water, like the ice it came from, does not do the work of carving the rock, it is the sediment it carries, but the Canadian Shield is made of hard stuff and it takes time to carve new channels in this durable granite.

Meandering rivers in glacial sediment

Meandering rivers in glacial sediment

Further south, the land is still flat, but has been overlain by a layer of sediment, left behind as the glaciers retreated.  Here rivers carve into the land more easily, looping back and forth and pinching off sections of themselves.  These oxbow lakes and the irregular rocky ones to the north are home to untold numbers of mosquitoes and other insects with aquatic life-phases.  These insects, when they emerge, lure birds from as far away as the southern hemisphere, and the mosquitoes become the bane of any humans wandering in the vastness of northern Canada during the warm season.  These insects, both adult and larval provide feed for numerous fish, making this an excellent place for fishing.  The first time my family and I drove to Alaska much of our food was from fish we caught each evening after only a few minutes with a line in the water.

The glaciers that covered the Canadian Shield were continental in scale.  There are only a few places where vast sheets of ice like that remain, but many places (for now) where small alpine glaciers are present, and even more places where signs of past glaciation are common.

One of the most famous of the post-glacial relics is Half Dome in the Sierra Nevada mountains of California.

Half Dome

Half Dome

The last interesting views I had out the window of my plane were of Half Dome, or Tis-sa-ack in the local native language.  This sheer rock-face is a batholith, a granite upwelling often making the core of a mountain.  Despite its appearance, Half Dome was not split in half, it seems to have formed more or less in the shape it has now.  Glaciers have smoothed and rounded the upper surface and carved out the characteristic U-shaped valley below though.

Glaciers have had a far larger impact on the world than most people realize.  Humans reached Australia some 60,000 years ago, able to walk over-land all the way to where Bali is now, needing boats only for a short stretch from Bali to Lubok.  Fifteen thousand years ago people walked from Siberia to Alaska over a broad grassy plain when the sea level was some 300 feet (91 meters) lower than today as a result of the water locked up in the ice.

When Greenland and Antarctica melt (which they will eventually do with or without our presence, the only difference is when it happens) sea level will rise by some 200 feet (67 meters) above present day levels.  At the moment there is a lot of talk of halting climate change via geo-engineering projects.  This is talk that completely and painfully misses the point.

The climate is a dynamic system, one that experiences wide changes over long periods of time, with the changes sometimes happening rapidly.  Yes, we desperately need to stop messing with the climate by releasing fossil CO2, methane, CFCs, and all the other greenhouse gasses we pump into the atmosphere with such abandon.  We are pushing the natural changes hard, forcing them to be of greater magnitude and to happen faster than they would otherwise.  We need to stop this, but what we do not need to and should not do is compound our mistakes by dumping iron into the oceans, pumping sulfur into the upper atmosphere, or place orbiting mirrors in space to deflect sunlight in a misguided attempt to keep the climate the way it was during the early 1900s.

We are driven by our economic system to keep things in some idealized stasis based on the time when we built our current infrastructure.  We may want things to stay static, but the earth is dynamic and fluid.  In our short-sighted, profit driven efforts to “save” our political and economic systems we will destroy the very thing that those systems and our societies are based on.

Seeing the earth from new perspectives and thinking about what we see tells us about the world is important.  We are on a cusp, we are standing on the edge of our metaphorical Half Dome.  We can tumble off the steep edge with disastrous consequences, or we can ease our way back down the slightly less steep slope, and once more enjoy the rich valley floor below.

Spring comes to Madrid

Spring is lurching its way through the Northern Hemisphere.  In Madrid this year this means more rain than has fallen since the 1940s, usually in a soft drizzle, occasionally spiced with small hail, bouts of hard rain, and periods of epic cloudscapes accompanied by bright sun.  It is familiar weather, reminding me of the part of California I grew up in.

In the countryside the effects of all this water are obvious, the land turns green.  This is likely to be a good year for farmers and wildflowers, though the former have a globally recognized habit of finding something to complain about no matter the weather.  For the wild plants this may mean bountiful seeds next year and the possibility of mast fruiting for woody plants that do that sort of thing (oak trees, I’m looking at you).

Within the boundaries of Madrid, where I have been living recently, the setting is considerably more urban.

The early evening view from a Madrid apartment

The early evening view from a Madrid apartment

In this landscape of stone, cement, and brick the effects of spring are more subtle and easy to overlook; they are most clearly seen in the length and material of coats worn by pedestrians.  Long black wool overcoats are being replaced by short black wool overcoats, leather jackets are replacing down, and on the few warmer days some of the women wear skirts with tights and accompanied by peculiar choices in footwear.

Nature-wise the heralds of spring are the street trees which are beginning to leaf out (especially the elms); ornamental cherries, plums, and almonds have been blooming, and, most interestingly to me, the little plants that have adapted to city life are beginning to show signs of life.

Leaves of an elm seedling

Leaves of an elm seedling

On the patio there is a planter box that has been left to what wild nature resides in the city.  A small elm has taken root and shows nice bonsai potential.  Accompanying the elm are, moss, English Ivy (planted), a few tender oxalis plants, and a small climbing vine with miniscule, but lovely, flowers; purple and white, kissed with egg-yolk yellow.

Leaves and flowers of our mystery plant - the flowers are perhaps half a centimeter across and at most a centimeter long

Leaves and flowers of our mystery plant – the flowers are perhaps half a centimeter across and at most a centimeter long

This plant starts out in a tight cluster and flowers prolifically when conditions are right.

A tangled clump of Ivy-leaved Toadflax (Cymbalaria muralis)

A tangled clump of Ivy-leaved Toadflax (Cymbalaria muralis)

This little plant, Ivy-leaved Toadfax (Cymbalaria muralis) is evergreen and originally native to the Mediterranean region, now found nearly globally, having been introduced both intentionally and inadvertently. The flowers betray the family association; snapdragons or Scrophulariaceae.

Cymbalaria muralis does not suffer from a lack of names, Coliseum-Ivy , Kenilworth-Ivy, Wandering-Sailor, Mother-Of-Thousands, Oxford-Ivy, Pennywort, and Ivy-leaved Toadflax being just a few of its common names.

Ivy-leaved Toadflax prefers calcareous soils and often grows directly from cliffs and older walls.  Here in Spain it is a native plant and is as much in balance with its environment as any other plant is in a land so heavily used by humans for so long as the Iberian Peninsula has been.  Elsewhere this small plant becomes aggressively invasive and can rapidly form a dense blanket of vegetation over trees, cliffs, and buildings.  It is a popular plant for rock gardens.

If a plant could be described as being clever, this plant might qualify for the compliment.  It sends runners out in all directions, with most of the ones I have seen pointing upwards.

Ivy-Leaved Toadflax climbing a trellis

Ivy-Leaved Toadflax climbing a trellis

On a healthy plant these runners can be nearly a meter long and have a fleshy, almost succulent aspect.  The leaves and the vines are slightly waxy and smooth to the touch, helping to limit water loss.  As it grows, Ivy-leaved Toadflax builds up a dense, nearly light impenetrable, layer of overlapping leaves.  Like a forest, this little clump of shade helps to trap both moisture and organic matter.  This little reservoir of nutrients feeds the ever growing plant.

The most interesting aspect of this plant is its behavior when it flowers and sets seed.  The flowers are pollinated primarily by bees and must be placed where the bees can find and land on them.  To ensure this the young flowerbuds are positively phototrophic; they actively seek out the brightest light.

Cymbalaria muralis flowers growing towards the light

Cymbalaria muralis flowers growing towards the light

Bees can see into the ultraviolet and to them flowers look very different than to us.  I am very curious how these flowers look to the bees.

Once the flower has been pollinated a change takes place and the forming seedpods become negatively phototrophic actively avoiding light.  The change can be quite dramatic and rapid

A fertilized bud running from the light

A fertilized bud moving away from the light

Avoidance of light sends the forming seeds into the darkest places within reach, places where it is more likely to find a safe, damp spot for the small seeds to be deposited.

Light and dark seeking stems

Light and dark seeking stems

This clever approach to seed distribution combined with rooting from runners and re-rooting from broken clumps serve the Ivy-leaved Toadflax well.  This change in light preference is not unique to Ivy-leaved Toadflax, the common houseplant Monstera deliciosa (aka Swiss Cheese Plant, Window Leaf, Mexican Breafdruit, and many more names) begins life avoiding light, then, when it finds a tree trunk its preference turns towards light as it climbs to the near canopy.

We don’t often talk about the behavior of plants, we usually use more neutral terms such as survival strategy.  To us plants are fixed in the landscape with their changes slow.  Plants lack of a brain makes discussion of behavior problematic.  We often fail to have an appreciation for the senses plants posses and they way their response to stimulus drives their growth and adaptability.  We have a prejudice for organisms with a central nervous system, or at least some form of mobility, because they are more similar to ourselves and we find them easier to empathize with.

The little Cymbalaria muralis is far from the only plant in flower right now in Madrid.  In the parks Common Fumitory (aka. Earth Smoke), Fumaria officinalis, is blooming.

Common Fumitory, Earth Smoke (Fumaria officinalis) flowers

Common Fumitory, Earth Smoke (Fumaria officinalis) flowers

Common Fumitory is in the Bleeding Heart family, related to Corydalis, Bleeding Hearts, and Squirrel Corn.  Often this pretty little plant is lumped into a sub-family of the Poppy family (Papaveraceae).

In some places small fields of Red Campion (Silene dioica) dance in the breeze, making rippling patches of purple-tinged pink.

Red Campion (Silene dioica)

Red Campion (Silene dioica)

In the countryside ground dwelling orchids are beginning to bloom, but I have not seen those yet.

Perhaps soon.

Into the forest at Lubuk Baji – Part 1: Hikes and Honey

The small Indonesian town of Sukadana, where I was to be living and working, is surrounded by Gunung Palung National Forest on a bit more than 3 sides and the ocean on the fourth.  The town rests in a small valley, and like many of the towns I saw in Borneo, it sits in the middle of what was once a mangrove estuary.

The hills surrounding the town are within the national park and supply the water that fills the estuary and the water that provides drinking water to the local population.

Gunung Palung NP wraps around Sukadana, to the east is a small hill names Lubuk Baji

Gunung Palung NP wraps around Sukadana, to the east is a small hill named Lubuk Baji

The harbor sits at the mouth of the estuary and had been cleared and hard-banked to support buildings and boats.

Sukadana Harbor

Sukadana Harbor

Like many such places there is tension concerning how to manage the local environmental resources, some want the hills taken out of the national park system so that they can be logged, others realize their value in maintaining the water table and wish to keep them protected in some fashion, others have different concerns.  Concerns focused more on biodiversity, especially of the large, rare local primates and of the incredible diversity of plants, insects, and animals in the region.

In general, the hills surrounding Sukadana are simply called the Sukadana Hills, but, as in most places, each place has a particular and specific name as well.  To the east of the town is a larger hill called Lubuk Baji.

The road there is narrow and bumpy, a raised affair passing between the numerous “wallet” houses, large buildings put up to house formerly cave dwelling swifts, the nests of which are harvested for bird’s nest soup.  The road passes through wet-rice fields and finally comes to an abrupt termination at a partially collapsed (or unfinished) brick building next to a shallow dam that keeps the flow of water from the hills to a judiciously controlled amount.  Behind the dam rice fields and coconut trees rest a the base of the Lubuk Baji hills.

Below the hills of Lubuk Baji lie coconut palms, rice paddies, and a small dam

Below the hills of Lubuk Baji lie coconut palms, rice paddies, and a small dam

The at the base of the hills surrounding Sukadana are groves of partially domesticated durian trees that we had heard the orangutan were visiting in search of the strong smelling ripe fruit.  For those of you who have never had durian, this is a large spiky fruit that a pungent odor that some liken to old socks and others to rich, sweet cream.  The texture of the fruit is like stringy custard and the flavor varies from person to person, ranging from a deep, lemony custard to green onions, to sweat soaked T-shirt armpit.  Those who like the fruit love it, and those who dislike it tend to hate it.  I am one of the few people who falls in the middle ground, to me the fruit is tasty, the texture and smell inoffensive, but I can’t see why such a big deal is made of it when there are fruits like mangosteen in the area.

Eating fresh, semi-wild durian in the Indonesian rainforest

Eating fresh, semi-wild durian in the Indonesian rainforest

The hike up to the top of Lubuk Baji was not difficult, though it was hot, humid, and steep.  At times we could smell orangutan, we found edible fruit dropped by these large primates, and several times we spotted their broken branch sleeping nests high above us in the canopy, but we did not see any orangutan.

There were a variety of interesting things to see other than primates along the way.

One of the most interesting to me was the remains of a honey harvesting operation.  The bees in this part of the world are large and make big, exposed honeycombs.  The heat is so great that the wax is in danger of melting, so the place the hives high in the trees hanging from the bottom of large branches where there is a breeze and they are sheltered from the sun.  The bees stand on the exposed comb and fan air over the wax with their wings when extra cooling in necessary.  The bees are usually fierce enough to chase away any animals seeking their honey, but humans have a particular love of sweet things and harvest the honey when they can.

This is a dangerous process as the bees pick only certain mature tree species.  These special trees are carefully protected by the humans and climbed when the honey is ready to harvest.  The hive may be 150 feet (30 meters) or more above the ground and the trunks of these trees are smooth and unbranched until the canopy.

Bamboo ladder hammered into the tree rising more than 50 meters into the canopy

Bamboo ladder hammered into the tree rising more than 50 meters into the canopy

Bamboo stakes are pounded into the tree and a set of bamboo canes is tied to the stakes with rattan strips, making a narrow and dangerous ladder to the canopy.  The lumps in on the tree in the photo are scars from a previous ladder put up perhaps 40 or more years ago.

At the top of the ladder the branches spread and the remains of old honeycomb can be seen clinging to the bottom of the branches from which it was harvested.

The reamins of honeycomb on the bottom of the branches above the terminus of the ladder

The remains of the honeycomb look like yellow stains on the bottom of the branches.  To the right the bees are building a new hive.

I was tempted to try climbing the ladder, but it seemed like a bad idea… no safety gear, uncertain footing, and a long climb up.  The people who climb up to harvest the honey must cope with those problems while being attacked by angry bees, carrying baskets and harvesting poles, and breathing smoke from fires lit below, the smoke of which is supposed to help confuse and stupefy the bees.

On the ground was an old piece of honeycomb, long since emptied of the tasty honey.

Old honeycomb, about 1 foot long (30 cm) long the long axis

Old honeycomb, about 1 foot long (30 cm) long the long axis

Coming up: Part 2 – seeing apes and monkeys in the forest.

Segovia: sandstones and granite

I have always loved things made of stone, especially ancient constructions.  The stone-masonry I have done has only increased my respect for the strength, vision, and talent of past masons.

Vermont garden wall

Small garden wall of Panton Shale for a friend in Vermont

Most of my stone projects have been small in scale.  The largest project was a 180 foot long retaining wall standing between 2 and 6 feet high, using 30 or 40 tons of stone.  That seems large when you’re doing it by yourself, but that’s a tiny project, barely larger than the little garden wall in the photo above.

In Peru there were some truly astounding pieces of megalithic engineering, many of them little known like Lanche and Kuelap, others well known like Saqsaywaman.

Walls at Saqsaywaman.  For scale zoom into the center of the full-size image to see the person.

Walls at Saqsaywaman. For scale zoom into the center of the full-size image to see the person.

Two days ago I went to the small Spanish city of Segovia and got to see several astounding pieces of stone-based architecture.  The first of these is the ancient Roman aqueduct.

The aqueduct in Segovia

The aqueduct in Segovia

The aqueduct runs about 15 km from the mountains into Segovia, with a 683 meter long raised section running through town.  The tall double arch of granite blocks is impressive enough by modern standards, even more so when you consider that it was built in the 1st or 2nd century, that the granite had to be carried in from the mountains, and that it is a dry-laid structure (no morter holding the blocks together) that has been standing for 1800 or 1900 years.  Clearly, this is a place with few earthquakes.

Granite is a favorite building material for many people.  It is an igneous rock that bubbles up in volcanic flows and cools in place.  The size of the crystals in the rock give an estimation of how long it took for the rock to cool and how much water there was in the melt.  The colors tell of the mineral content.  This granite is pale, with moderately large crystals weathering out, leaving the exposed stone extremely rough to the touch.

Due to the way it forms granite has no preferential cleavage plane, meaning that, given the right tools, it is easy to shape into whatever form is needed.  It is a dense and strong rock as well, another reason it is often used as a foundational material.

The blocks of stone making up the aqueduct are large, not enormous, but large, hundreds of pounds each.  At its highest point the aqueduct is 29 meters tall (that’s about as tall as a 4 or 5 story building).  Nearly 2 thousand years ago those blocks had to be hoisted up and set in place.  Clues as to how the Romans did so are carved into the blocks.

Lifting divots on the granite blocks

Lifting divots on the granite blocks

Each block was lifted into place with a pair of metal pincers, like those people used to carry ice-blocks with.  Divots were carved into the stone to prevent the pincers from losing their grip.  Presumably the divots were carved at the balance point of the block as well, a calculation I would be very curious to know how was done.

Supposedly Segovia was a “small outpost” when the Romans ran things in the area, though the effort and cost of building the aqueduct makes me question that assessment.  Small outpost or no, very little happened in the area for a long while, then in the 1200s the town began to grow and with that growth came the buildings that Europe is so well known for.

Castles and Cathedrals.  Segovia has impressive examples of both, the castle being the inspiration for Walt Disney’s version of Sleeping Beauty, and the cathedral being on the of the last of built of the great Gothic cathedrals.

Segovia cathedral

Segovia cathedral

Construction of the cathedral began in the 1500s, but took more than a century to complete.  The massive building looms over the city, glowing golden in the sunlight.

The first thing that struck me was neither the size nor the the tremendous amount of fine detail.  It was the color.  A warm, yellow/orange, not the color one associates with Gothic architecture, or with goths in general.  The castle, cathedral, and much of the rest of Segovia is made from this stone, not from the granite the aqueduct is made from.

The town of Segovia rests upon an outcrop of calcareous sandstone (sandstone with the grains cemented together by calcium rather than silica) and the land around rises and falls, exposing the bedrock in numerous small cliffs.  Sandstone is a sedimentary rock, a class of rock at the opposite end of the formation spectrum as granites and other igneous rocks.

Sandstone tends to have horizontal cleavage planes, refection the initial depositional patterns, and is often soft and easy to carve.  The sandstone in Segovia seems made for carving and the cathedral  builders took full advantage of this.

Cathedral detail carved from sandstone

Cathedral detail carved from sandstone

Sandstone weathers and erodes easily, especially in the presence of water.  Segovia, despite being a dry region by my standards (about a half meter of rain per year) is considered a wet place in comparison with nearby areas.  As such the builders took pains to protect the soft sandstone, making their waterspout gargoyles of the more resistant granite.

Cathedral gargoyle rain-spout

Cathedral gargoyle rain-spout

Statues of sandstone have not weathered as well as those of granite.

A royal lion slowly weathering away

A royal lion slowly weathering away

The the level of fine detail in the cathedral architecture is reflected elsewhere in the town.  The older buildings and the castle are covered with patterned façades.  In the past these patterns seem to have indicated which family owned the building and in a few cases older patterns could be seen under the more recent ones.

Old wall pattern, the material looks and feels like reconstituted sandstone.

Old wall pattern, the material looks and feels like reconstituted sandstone.

The castle, the Alcázar de Segovia, has a more simple pattern, but each intersection is studded with fragments of volcanic rock.

Looking up the castle wall to the battlements.  the small black studs are fig sized pieces of vesicular volcanic rock brought in from far away.

Looking up the castle wall to the battlements. the small black studs are fig sized pieces of vesicular volcanic rock brought in from far away.

Like many European castles the one at Segovia has gone through a number of iterations; fort, castle, palace, prison, artillery college, and museum.  It still serves the latter two roles.

The castle commands a wonderful view of the countryside in all directions.  One of the most magnificent views is of the cathedral:

Segovia cathedral from atop the Alcázar de Segovia battlements

Segovia cathedral from atop the Alcázar de Segovia battlements

In the opposite direction an old Templar keep and the sandstone cliffs much of the stone was quarried from to make the city are visible.

Templar keep and sandstone cliffs above the river below the castle

Templar keep and sandstone cliffs above the river below the castle

This has been a less science based post than most, but the trip to Segovia was far too interesting to keep all to myself.

The castle, aqueduct, and cathedral are the largest of the attractions, but not the only ones by far.  The food is delicious, mockingbirds flit about the city, interesting small plants grow from the old walls and on the red tile roofs, and great architecture abounds.

Small church in Segovia

Small church in Segovia