Aposematic
A zoological term applied to usually bright colouring or markings designed to warn or alarm, and thus to repel the attacks of predators.
According to the OED the first recorded use was as late as 1890 and the word is derived from the Greek ἀπό apo away + σ̑ημα sema sign.
Wasps are a fairly classic example of aposematic marking.
Category Archives: natural history
Weekly Photograph
This week I bring you a really poor quality shot, but one for the record. n Saturday lunchtime we had a fox in the garden. This isn’t unheard of, even in daylight, but it isn’t something we see more than about once a year. But on this occasion Mr Reynard hung around for quite a while — maybe 15 minutes — sniffing around the garden and finding the odd tasty morsel which the starlings have missed. So I managed to get a few, not very good, photos. They’re poor partly because I was shooting through the study window, and the window is grimy hence the slight mistiness; but I knew if I opened the window this would be enough to scare the fox away.
Reynard the Fox
Greenford; November 2015
As you can see, Reynard was in pretty good condition — as (s)he should be given the mildness of the weather. What was striking though is the paleness of the coat on the body and the conspicuous black ears and paws.
Weekly Photograph
This week another from our recent short break in Rye. On the way hope we detoured via Dungeness — such a wonderful expanse of shingle and environmentally hugely important. As might be expected there was a lot of sea kale growing; this is one particularly splendid example. But, yes, I’ve tinkered with the photo to make it even more dramatic!
Sea Kale at Dungeness
Dungeness; September 2015
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Weekly Photograph
This week’s photograph is one I took last week. We were in Rye for a few days and perusing the showroom of Rye Pottery. I looked in a large bowl and couldn’t help but see this enormous Tegenaria spider — probably Tegenaria parietina but there are several very similar species. The body was around 1.5 to 2cm long and the whole thing, as seen, about 10-12cm across.
Tegenaria parietina?
Rye; September 2015
These spiders live in buildings — especially old buildings — and walls. Females can live for up to eight years, while males die shortly after mating. They are actually quite harmless to humans.
I know many people don’t like spiders, but how can you not be impressed by a stunning creature such as this.
Your Interesting Links
And more, and more, and more
Yes, we are doing well at present for interesting links to items you might have missed the first time round. Here is the latest instalment, and again I promise you nothing too hard by way of science!
What is it that makes wet dogs smell so? Here’s a brief look at some of the chemistry.
There are definite advantages to being female, and if you’re a cat one of them is that you can have splotchy fur.
Most moths can only make noise by rubbing their legs or wings together, but the Death’s-Head Hawkmoth has a built-in flute. They also eat honey.
We all know that seeds can last a long time just by observing what happens when you turn over an undisturbed piece of ground. But how long can seeds really survive?
And from seeds we’re now on to food … We’re often told that western society eats too much meat and we should cut back. While this would undoubtedly be good for our health, can meat ever be eco-friendly?
Have you ever stopped to think about what cooking oil you use? Well some scientists have and the results may surprise you.
Scotch eggs originated in Scotland, didn’t they? Except they probably didn’t.
Who has ever had hiccups after a meal? Or maybe some other time? But why do we hiccup?
So now to some different aspects of lifestyle. What (if any) are the scientifically proven benefits of yoga? Julia Belluz looks at all the evidence.
I wonder how many of you already know these 9 facts about breasts? No, I didn’t!
How to improve your work-life balance by doing one simple thing? You can’t? Oh yes you can! It sometimes takes a bit of discipline, but I did it many years ago and it worked for me.
Next a couple (more) items — here and here — on why family nudity is actually healthy for kids. Girls especially are more likely to grow up with a good self-body image.
And now a quick shuffle across to the history room where first we find a piece on a little known relic of early 17th century London: the York House Water Gate.
Slightly later, but still on the Thames, a piece on the creation of the St Katharine Docks and how they changed the working of the docks.
And finally, from boats to trains. Here’s the low-down on the ghost trains of Britain.
Oddity of the Week: Victorian (Medical) Oddities
Warning: not for the squeamish.
Conjoined piglets and two-faced kittens! Oooo-eerrr!
In the 19th century, bodies (both human and animal) were hard to come by, so medical and veterinary schools abandoned many dissections and taught their students using remarkably odd objects like waxwork embryos and exploded skulls as well as preserved specimens like this octopus.
The Guardian has a gallery of more interesting examples at www.theguardian.com/artanddesign/gallery/2015/jul/09/victorian-oddities-two-faced-kittens-conjoined-piglets-in-pictures
Enjoy your lunch!
Orchid Instructions
Yesterday I posted a photo of a Denbrobium orchid, and in the past I’ve posted images of Phalaenopsis orchids. Yesterday I also made the comment that orchids are very easy to get back into flower, but realised afterwards that most people aren’t going to have a clue how to do this. So instead of throwing out that beautiful orchid once it has finished flowering, this is what you do …
Phalaenopsis orchids, which is most of what are in the shops, are actually surprisingly easy if you do a few simple things. You will also sometimes find Dendrobiums and in my experience they can be treated in much the same way. (There are many other species of orchid but these are the ones you will normally find on general sale, eg. in supermarkets, in the UK.)
Phalaenopsis orchid
Orchids are epiphytes which grow in trees using their roots only to hold them lightly in place and to pick up water. They will also grow extra aerial roots to absorb any moisture in the air; these roots should not be buried in the compost. Good roots are essential for flowering.
Make sure your orchid is potted in bark chippings and NOT in soil or moss. Orchids must not stand in water or be waterlogged; their roots have to be free-draining. If your orchid is planted in anything other than bark chippings, get some orchid compost (which is basically bark chips) and repot it. Being waterlogged is the quickest way to kill an orchid.
Dendrobium orchid
You’ll notice that most orchids are planted in transparent or translucent plastic pots. This is because their roots like light just as the leaves do. If possible keep the orchid in a light place and in a clear container.
Do not put your orchid in bright sunlight as this is likely to scorch the leaves. They are plants which grow in amongst the branches of trees so although they need good light they would only naturally get dappled sun.
Orchids also need to be warm (20-25°C) most of the time. Avoid putting them somewhere where the temperature fluctuates a lot and keep them out of draughts. However a few weeks of slightly cooler temperatures (maybe down to 15°C at night) and reduced watering forces them to rest and is almost essential to get them to come back into flower.
It is a good idea to get some orchid feed. There is a “Baby Bio” orchid feed in a pink bottle; it is easily available — many supermarkets sell it — and is probably as good as anything specialist. A bottle will last a long time.Now about watering. Your orchid needs watering once a week but it must NOT stand in water all the time. Each week put your orchid (in its plastic pot) in a bowl and fill it with water almost up to the level of the compost. If you have orchid feed add a small squirt of this to the water (read the directions on the bottle) although this should not be done every time they are watered. Let the orchid soak for an hour or two (but no more). Then take it out, put it back in its outer container and return it to its normal place.
Watering time is also a good opportunity to give the plant the once over. Remove any dead/dying leaves, dead flower spikes and dry shrivelled roots with a pair of sharp scissors. Try to make sure the leaves are clean and dust free. Keep an eye out for pests like scale insects — if you spot them I’ve found that unfortunately the only reliable way to get rid of them is with a houseplant insecticide spray.
When your orchid has finished flowering — hopefully after many weeks as the flowers can last 6 weeks or more — remove the dead flowers and cut off the flower stem of Phalaenopsis (with Dendrobiums you should only remove the flowering stem when it dies and withers). Keep the cane which was supporting the flower and any clips or ties. If it needs it this is a good time to repot your orchid.
Another of my Phalaenopsis orchids
Don’t worry if your orchid isn’t growing lots of new leaves. Phalaenopsis grow very slowly, usually only one or two new leaves a year. Dendrobiums will throw up new stems quite easily; these may need staking and they should eventually flower.
Your orchid will flower again but normally it needs those few cool nights to trigger this. As the spike grows you should stake it (that’s why you kept the old stake and clips). Although the stems themselves are quite robust, they do tend to fall over with the final weight of the flowers and it is easier to keep stems upright if they are staked early and trained upwards.
Then just sit back and enjoy the wonderful flowers!
Weekly Photograph
This week’s photograph is a wild flower, Red Campion, which was growing in the woodland burial site where we interred my mother last week. It is just a small taste of how delightful a place this is.
Red Campion
Colney, Norwich; June 2015
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Weekly Photograph
Noreen found these two feathers in the garden yesterday afternoon. They are from a Greater Spotted Woodpecker. The top one, a secondary wing feather, is about 8.5cm in total length. The lower is a primary feather. Note the feathers come from different wings, as they curve in opposite directions.
GSW Feather
Greenford, June 2015
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Fruit Fly
I was looking at a fruit fly (actually probably more likely a fungus gnat or sciarid fly) a couple of days ago. It was about 2mm long walking up the side of my tea mug.
Aside from the ability of flies to walk up vertical, shiny surfaces (and indeed walk upside down on the ceiling) I marvelled at how Nature can make something so tiny which can function at all.
Look at the legs. They’re as fine as silk. How do you pack into such a tiny diameter an exoskeleton, muscles, nerve fibres and some rudimentary circulation? It defies belief.
And the antennae are much the same. And the wings.
What’s more … How on earth does anyone dissect such a leg or wing to understand the structure? I just cannot get my head round that. Just how do you do such delicate work?
It does make one see how people can believe in intelligent design — for surely engineering something this intricate just isn’t possible. And yet that is exactly the marvel Nature has achieved via evolution.
Incredible!