Monday, August 29, 2016

Featuring a red squirrel and a 7ft hedgehog...

EDIT: 03-10-2016
Apologies if you have received a notification of this update by mistake.


Following my last, rather dark update, I thought it was time to lighten up here a little and change the mood...


And remember; wherever you are in the world, and I know my little blog is read in at least 10 countries, we all laugh in the same language!

  Stats for my last update        

Just a thought: this is also ironic if you are smart enough?

This is a photograph of a female Misumena vatia crab spider that I took the other day. It is this species that can change colour from white to yellow and visa-versa. Whilst we are making merry with this particular update, perhaps it would be pertinent to mention that 'visa-versa" is also the title of a musical offering by German duo 'Funkstörung'. No? Well it made me chortle; I'm sure it must be an anagram of something rude!

The yellow version...
I guess this won't be the case right across our British Isles, but here in Kent the last few days have been hot and very humid. I am not complaining of course; we have waited far too long for a taste of summer. It has left me feeling a little sluggish though...

Arion distinctus (probably)
Yes it was a hot summer day when I photographed the slug; I hadn't intended such an exotic subject of course, but in the heat, it was all there was about. It really was a 'somnolent summer day', as they say (whoever they are).

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I know what you have been dying to ask me...

"What’s the difference between a pupa, a cocoon and a chrysalis?

How strange that you should ask me this at a time when I have been thinking about it too; here then, in layman's terms, is my very bestest go at an explanation:
 Pupa and chrysalis have the same meaning: the transformation stage between the larva and the adult. While pupa can refer to this naked stage in either a butterfly or moth, chrysalis is strictly used for the butterfly pupa. A cocoon is the silk casing that a moth caterpillar spins around it before it turns into a pupa.

All of which is a sneaky way of linking to this small white chrysalis that I happened upon a while back...
Pieris rapae pupa (green form, there is also brown)

I was able to witness this struggle to be free of the chrysalis casing when the adult butterfly emerged...
Pieris rapae
It did eventually manage to extricate itself, and after a good long rest to recover from all the exertion, was on its way. Which is all good news of course, but, I know what you are thinking now: what does 'layman's terms' mean?
Why ask me? I am just a humble country boy, my knowledge is finite. Alright, I will have a bash as they say (there they are again).

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Let's start with the word layman: a person without professional or specialized knowledge in a particular subject.
Plain English (or layman's terms) is a style of communication that is easy to understand.

Back to the subject in hand then. The subject in my hand right now is 'BB' and I don't mean Bridget Bardot (ask grandad), nor Billy Bragg, neither Betty Boo. Nope, I am talking of the insect alliteration, Bumble Bee...

It seems to have been a good year for BB's this year



'In the pink'...there's another little saying that has me wondering about its origin. Whilst I wonder, here's a pink bug...

Eurygaster testudinaria



Not really a pink bug of course, only at this stage of development following a moult.

Maybe this next picture can out-pink the tortoise bug?

Mimas tiliae larva
It's another shot of the lime hawk-moth larva from a few weeks ago. Enough pink do you think? Me too; I am starting to see red!

Sciurus vulgaris
I was lucky enough to get a couple of hours at the British Wildlife Centre in Surrey recently and I spent most of my time in the red squirrel enclosure.

They have this huge, sculpture I suppose you would call it, of a hedgehog at the entrance to the park. It is 7ft high and was built by UKTV to mark the second series of David Attenborough’s Natural Curiosities. 


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Here is what the adult tortoise bug will look like once it has coloured up, just in case you didn't know, which I am sure you did...


And at the other end of the scale, a teeny early instar of the same species...



Smaller still, by quite a margin actually, was this springtail...

Allacma fusca I think
One final photo for this update; a froggie...




Sunday, August 21, 2016

The vexation of a vexillologist...

Isn't it great when you get to learn something new. I recently found out what a vexillologist is!

But I am already getting ahead of myself, let me backtrack a little.

I am always upfront about the fact that I am not an expert on insects and bugs. Far from it, I am merely an amateur with an interest and inquisitive nature. It's true that over time you are able to accumulate (and hopefully store) facts and figures about some of the bugs you might encounter on a regular basis, but even so, there is always more to learn and somebody who already has a superior knowledge.

Having said all that, there is always research and I try to use that tool whenever I find myself lacking, which is usually more often than I would wish.

 Here's an example: the Large White, or Cabbage White Butterfly (Pieris brassicae). It was whilst researching the parasites of  this species that I stumbled upon Dr Tom Williamson and his excellent blog post entitled: Cotesia glomerata: an amazing example of what evolution is capable of. Dr Williamson describes himself amongst other things as an amateur vexillologist.


I had to look it up in the dictionary to satisfy my curiosity. Just in case you don't know either, I will share in a little while, but first, back to the butterfly caterpillars and their parasites......




A Large White Larva
When I recently witnessed a greenhouse full of these larvae, I assumed that there would be some that had been invaded by a parasitic wasp; I also assumed that it would probably be Trichogramma brassicae. But here is where my knowledge of such things was found wanting. It seems that T.brassicae infects the eggs of the butterfly, rather than the larvae. 



Just before I move on to the real culprit, there is a fascinating story attached to the Trichogramma wasp, that I will try to abridge, as I am sure you have better things to do than spend all day on my little blog.

When the male Pieris brassicae mates with a female, he tries to ensure that she will not then go on to mate with other males. One trick is to transfer pheromones that act as anti-aphrodisiacs, in itself a marvel of nature. But even that can be 'out-natured' by the fact that the very same pheromone is known to attract female T.brassicae wasps. Once the female wasp finds her targeted, and now pregnant butterfly, she  hitches a ride on her, and as soon as she lays her eggs, the wasp gets off and injects her own eggs into the butterfly’s eggs.

Meanwhile, the real miscreant is Cotesia glomerata. Miscreant is possibly a tad defamatory on reflection though? After all this is nature and a natural behaviour, no matter how bizarre or deviant we consider it to be. 

The Cotesia glomerata narrative is every bit as fascinating as the previous contender, as I discovered, and you are about to: assuming you don't already know that is...

Dozens of wasp larvae emerging from the stricken, but still living caterpillar


You see the cabbage (and other) plants that host the caterpillars are fighting back! There is a kind of co-evolutionary race betwixt the caterpillar and the plant: as the caterpillar evolves better ways to feed, the plant evolves better ways to defend itself, so the caterpillar evolves ways to counter etc...etc. 



The parasitised caterpillar protecting the wasp larvae

As the plant reacts to chemicals produced by the larvae, it begins to produce chemical elements that act as an indirect defense by attracting the female C. glomerata wasp, in the same way that the pheromones of T.brassicae do. This wasp is a rather devious parasitoid that finds the  youngest caterpillars feeding on the more nutritious top leaves.This means that the caterpillar will be a better living larder for the young. She will then lay 2 or 3 dozen eggs inside each caterpillar. To return to Dr Williamson's words.."I find this species to be an incredible example of evolution at work. Not only does the larvae of the wasp feed off of the caterpillar host, but after they bite their way out and make cocoons, the host caterpillar spins it’s own cocoon over the larvae, and protects them until it starves to death! Yes, it could be considered pretty gruesome, but fascinating nonetheless."  (© 2016 The Skeptic Canary)


Here is a little video I took of the emerging wasp larvae... 


Note: These vids are too large to show in the email version of my blog. Hence you will need to view the blog directly online.




And at the end of all that, what did I discover a vexillologist to be? Quote: Vexillology is the scientific study of the history, symbolism and usage of flags or, by extension, any interest in flags in general. The word is a synthesis of the Latin word vexillum ("flag") and the Greek suffix -logia ("study.")