Evolution before my eyes

Dog minding has its advantages. It gets you out to the beach in the early hours when it's empty apart from a very few other dog lovers.

The sea was calm, the sun was warm but had yet to get hot enough to make exercise an effort.

Terns were fishing out on the bay, too far out to distinguish species. It was the same with a group of divers – birds that is, not sub aqua enthusiasts though we get plenty of those as well.

The fact that there were four together made me think they were black-throated divers which do sometimes gather in groups in the summer but, without binoculars, they were just divers.

These summer visitors are a welcome sight especially in a year when we have had so few swallows and house martins.

Common, Arctic, sandwich, little, or roseate terns must have all had a common ancestor before they evolved into their specialised species and so with great northern, red-throated and black-throated divers. or swallows, sand-martins and house-martins.

Darwin went to the Galapagos and studied the finches on the different islands before the penny dropped that they all arose from one original stock and yet it is plain to see, all around us, once the idea of evolution of species is accepted.

Following the burn up from the beach, I came across another visitor that has made its home here.

The monkey flower. Mimulus guttatus, which apparently started off as a wild flower in North America.

With one hundred and sixty different variants from annuals to woody-stemmed small shrubs, the mimulus species has become a leading model system for studying ecological and evolutionary genetics in nature.

A marmalade hover fly follows the "landing strip"  of red markers leading to the nectar and the pollen

There is to be an expedition to The Cradle of Storms, the remote Aleutian Islands off Alaska, to try and prove that the ancestor of the Scottish variety of monkey flower arose there and was brought back to Europe by a Russian -German explorer, Grigori von Langsdorff, in the nineteenth century.

There they were, growing in our burn, apparently a master of adaptation.

Evolution on our doorstep.

Bridges and castles

Under the bridges up the river path

The lap-top had to go to the local computer expert to get some glitches fixed. Computers are a bit like modern cars. Most of us use them daily to make all sorts of digital journeys to the shops, the bank, the library, even to the doctor's sometimes, but we haven't much idea what makes them tick so when they stop, it pays to get an expert opinion rather than tinker by yourself.

Waiting to collect the item, I spent a pleasant hour strolling along the banks of the Tweed from the Old Bridge built in the early seventeenth century to the Royal Tweed Bridge, which replaced it in the early twentieth century.

Looking up from the path, I could see the looming walls of the splendidly intact Elizabethan walls around the town.

 The great swan herd that gathers on the tweed estuary in the autumn was diminished presumably by the availability of food and nest sites upriver but some remained to glide seamlessly beneath the arches with the flow of the current.

The Royal Border Rail Bridge from the gun slit of the riverside guard-house

Further up the river the East Coast mainline crosses on the Royal Border Bridge, a magnificent viaduct carrying the railway to and from Berwick station.

The railway skirts the ramparts of Berwick's fortifications but the castle built by King David in the thirteenth century to protect what was then the major Scottish port, was in the way so it was demolished. The Great Hall where fate of the Scottish crown was decided is now a platform with an information board. 

The remains of the curtain wall - the White Wall - and a tower with gun-loops to guard access to the river are all that remains. After three hundred years of warfare between the Scots and the English when it changed hands many times and three hundred years of united peace, the castle had to make way for the railway.

The castle as it was with the guard house on the riverside

In the nineteenth century the impact of the railways must have been as encompassing as that of the internet today. Isolated villages where things had changed little since Jamie the Saxth of Scotland went south across the Tweed to become James I of the United Kingdom, now had access to and information about the wider world.

The internet has connected people all over the world in the way that the railways connected everyone in the country.

I can just carry it about on a phone or a laptop and ancient piles are safe.

 Someone created this whimsical boat from driftwood

... and there in a wood a piggywig stood

 

Beech trees and pignuts in the Dell

The Dell is one of my favourite spots. A little wood along the banks of a burn, mostly beech and ash trees, it was almost certainly planted in times when the estate and farms surrounding it would have been self sufficient in raw materials. Ash for tool handles, building and fuel, beech for pannage, fodder for pigs.

Others appreciate the quietude of the Dell

 Pigs thrive in woodland especially on beech mast. I've no doubt that the wood was planted more than a century ago with pigs in mind.

The reason I'm so sure is the abundance of pig-nut, conpodium majus, growing on the woodland floor.

Conopodium majus

 They are a fairly common plant, an indicator of long established grasslands.

The delicate leaf fronds and the creamy white flower heads are not what the pigs like. It is the nut or tuber at the end of the long root that is so attractive. At one time country folk especially children would dig up the nuts to eat. They are a bit like hazel nuts or sweet chestnuts to eat but, as they aren't nuts, they have no hard shell. They seem to be a sort of tuber

The  pig nut or the earth nut

Their presence was probably the reason for the planting of beech trees in the Dell. Unlike ash, beech don't spread seed easily and are usually a deliberate planting. Someone thought, "add the beech to the pig nuts and we've got a great place for pigs to forage and fatten for free"

Pig-nuts or earth-nuts are sometimes called St Anthony's nuts after the patron saint of swineherds!

Now the local pigs have a much more organised lifestyle. They still live out with their offspring in amenable surroundings but they have a diet of concentrated food pellets from hoppers to ensure a predictable end product.

There is one little day-flying moth that relies entirely on the pig-nut for food for its caterpillars. The chimney sweeper moth is black with white edges to its wings. There were none flying the day I was there but they do prefer bright sunshine, a commodity in short supply of late.

There are no pigs rooting about in the Dell now but that does leave more pignuts for the chimney sweepers

 Shakespeare must have grubbed up pig nuts as a child for he understood the difficulty of finding them at the end of the long, easily broken root

"I prithee, let me bring thee where crabs grow; and I with my long nails will dig thee pignuts"*

Crab apples or scrogs as the Scots would call them were also planted where the pig-nuts grew to provide food for pigs.

*  Caliban in The Tempest.