The pharmaceutical poppy

There was no mistaking the identity of the Yellow Horned-poppy (Glaucium flavum)  scattered liberally along the shingle of nearby Slapton beach last week. The large yellow flowers are dwarfed by the extravagant sickle-shaped, horn-like seed pods that grow up to a foot long.

This predominantly coastal plant has been adopted for centuries as a traditional medicine, including use by the Vikings of Norway and Denmark (Psychoactive Herbs, 2012).  Over more recent decades, scientists have developed techniques to extract alkaloids from this plant, the main representative being glaucine (named after the plant). This has led to pharmaceutical use in drugs as a cough suppressant, anti-inflammatory and analgesic. There has also been a degree of recreational use due to its opiate like effect (Psychoactive Herbs, 2012).  A more innocent application is as a fuel for lighting by using oil from the seeds (PFAF, 2012). A recent development is the use of glaucine based creams as a cosmetic treatment for cellulite. The glaucine appears to impact fat cells by causing them to release fat as well as inhibiting new fat cells in favour of collagen-producing cells, resulting in “fat being replaced by firmness” (Lipotherapeia, 2012).

So as the Vikings landed on British beaches did they seek out the Yellow Horned-poppy to; stop coughs, get pain relief, have some fun or simply to firm up their buttocks?
 

Lipotherapeia (2012) Is glaucine, an extract of the common yellow poppy, the ideal anti-cellulite cream ingredient? [Online]  http://www.lipotherapeia.com/cellulite-questions-answers/is-glaucine-an-extract-of-the-common-yellow-poppy-the-ideal.html [Accessed 13/07/12]

Psychoactive Herbs (2012) Yellow Horned Poppy Extract, Glaucium flavum. [Online]  http://psychoactiveherbs.com/catalog/index.php?cPath=170_193 [Accessed 13/07/12]

Plants for a Future (PFAF) (2012) Glaucium flavum – Crantz. [Online]   http://www.pfaf.org/user/plant.aspx?LatinName=Glaucium+flavum [Accessed 13/07/12]

The pretty hungry caterpillar

We have been watching a group of very colourful caterpillars in the garden over the last few days. Many of you will recognise these caterpillars from the image, but perhaps have wondered what species it is and whether the adult is equally visually stunning. A strong clue to the caterpillars identity is its favourite food plant, Mullein, and hence its name the Mullein Moth (Shargacucullia verbasci). Our particular caterpillars featured are feeding on Great Mullein (Verbascum Thapsus) with its distinctive velvety elephant ear-like leaves - or what’s left of them. This moth will also feed on other Verbascum species, but also Figwort (which I have more frequently observed) and Buddleia.

The caterpillars seem unconcerned with their high visibility ‘jackets’, almost advertising their bright yellow and black markings – this is presumably to warn any predators not to eat them because they taste bad. This stunning colouration is in stark contrast to the adult moth form which at rest appears to mimic a dead plant stalk.

Many gardeners are all too acutely aware of how prone their Verbascums are to attack by the caterpillar of the Mullein Moth, which can consume much of a plant's entire foliage in a day. I counted only about three caterpillars on our Great Mullein and today we are left with little more than a stump. However this is where their colouration works against them as they are easy pickings for green-fingered predators!

A Lizard's tale

A few weeks ago I was lucky enough to spot a Grass snake (Natrix natrix) crossing our local country lane. I managed to grab it momentarily to get a good look before releasing it into the hedge. Then last week during the warmer weather I spotted another much smaller snake-like animal, a Slow worm (Anguis fragilis)- the Anguis is taken from the Latin, 'slim' and 'snake'. However, as many of you will know it is not a snake, but a legless lizard, being distinguishable by its closable eyelids which is why it is also called the Blind-worm – snakes do not have any eyelids.

This particular specimen was behaving rather too true to its name, being rather sluggish and easy to catch. I was concerned about its safety as we have a high cat population locally, one of its not uncommon garden predators. Like other lizards the Slow worm does have a curious defence, the ability to lose its tail to escape predation using a mechanism known as ‘caudal autotomy’. By detaching a section of its body that then independently writhes vigorously it distracts its predator whilst it makes its more genteel escape. Perhaps it is this tail breaking trick that provides the ‘fragilis’ part of its Latin name. I have witnessed this phenomena and it is quite a sudden and amazing sight, with the tail demanding attention. Theseverance of its tail is a reflex achieved using a fracture plane (‘line of weakness’) in the caudal vertebrae. However it can only do this once and the new tail grows back significantly shorter than the original (Fuke, 2011), and can take several years (Bryant & Bellairs (1967). Despite the immediate advantage of surviving an attack, the tail loss has potential significant costs such as reduced locomotion and it has been shown to have a negative impact on reproductive success (Maginnis, 2006).

This all leaves me pondering the question, how does an individual Slow worm that can live 20 years plus determine the significance of every one of the many threats it will experience and decide on each occasion whether to play its one 'joker’.

Bryant, S.V. and Bellairs. A. (1967) Tail regeneration in the lizards Anguis fragilis and Lacerta dugesii. Journal of the Linnean Society of London, Zoology, 46(310): 297-305

Fuke, C. (2011) A study of a translocated population of Anguis Fragilis in Cornwall, UK. The Plymouth Student Scientist,4(2):181-221

Maginnis, T.L (2006) The costs of autotomy and regeneration in animals: a review and framework for future research. Behavioral Ecology, 17(5): 857-872.

Classy jumper

The recent improvement in the weather has triggered a burst of insect life as they respond to the early summer heat. This has shifted the hazards as I run the local lanes, from leaping giant puddles to avoiding swallowing the local insect fauna. Whilst on a slower ecological circuit, I was drawn to the numbers of flies, beetles and bees feasting on the abundant Alexanders flowers and other plants. It was however a red and black ladybird-coloured insect that particularly caught my eye, poised on a nettle. I took a couple of images before my macro lens became too intimate with the beast and in a flash it was gone. Back at home I was quickly able to identify it as one of our most visual frog hopper species, the Red-and-black Froghopper (Cercopis vulnerata). These bugs are also known as ‘spittle bugs’ and cuckoo-spit insects’, due to their nymphal stage habit of living in a protective mass of froth or spittle (Chinery, 1977).

When it comes to jumping stakes, few would bet against the flea when taking account of relative body weight. It turns out that froghoppers, such as C. vulnerata, produce a substantially better jumping performance. Starting with my puddle leaping efforts with a take-off force of about 2-3 times my body weight, the flea manages about 135 times, and froghoppers more than 400 times (Burrows, 2006). This is a very useful if you want to avoid predation or being eaten by a grazing cow. Researchers have shown that the key to this jumping performance is a spring-loading mechanism called the ‘pleural arch’, which the insect compresses like an archer’s bow in readiness for leaping to safety (Patek, et al., 2011). It is even cleverer than this when you consider the materials used to form the pleural arch; a sophisticated combination of chitinous material to store energy and ‘resilin’ to provide flexibility and shape restoration, has drawn comparisons with high performance composite bows (Patek, et al., 2011).

Such innovative mechanisms adopted by insects has inspired engineers and biologists to consider applications for human inspired devices. If we get another wet spell as bad as this April, I would be interested in a ‘human friendly pleural arch’ device to better avoid the puddles.

Burrows, M. (2006) Jumping performance of froghopper insects. Journal of Experimental Biology, 209: 4607-4621.

Chinery, M (1977) A Field Guide to the Insects of Britain and Northern Europe. London: Collins.

Patek, S.N., Dudek, D.M. and Rosario, M.V. (2011) From bouncy legs to poisoned arrows: elastic movements in invertebrates. Journal of Experimental Biology, 214:1973-1980.

Limestone lovers

Berry Head in South Devon is quickly becoming one of my favourite haunts with its rich botanical landscape and marine wildlife. Last September I blogged about one of its specialities, the White Rock-rose (Helianthemum apenninum), a nationally rare species (see http://nicksnaturenotes.blogspot.co.uk/2011/09/last-white-rock-rose.html). The unusual mix of physical geography and chemistry provided by the Devonian limestone sea cliffs of Berry Head provide conditions for the White Rock-rose shared only by a handful of other sites in the South West. I was visiting it again this weekend with friends and showed off the White Rock-rose amongst other more common plants. Towards the end of the afternoon we wandered up to the remains of the fort in search of summer migrant birds amongst the scrub. Resting my arms on the battlements and enjoying a Whitethroat and possibility of Cirl Buntings, I became curious about a stunted-looking plant which I had almost leant on. Closer inspection revealed what looked like a bonsai version of an umbellifer, a dwarf parsley or carrot plant. My companion with much pleasure eventually identified it as Honewort (Trinia glauca), which is indeed a member of the carrot family and another local limestone specialist. Apparently, in turf closely grazed by rabbits, plants of Honewort grow to no more than a few centimetres tall (BRC, 2012), as was the case with many of the Berry Head plants that we observed.

When I got home I looked at the distribution map on the National Biodiversity Network's Gateway (see http://data.nbn.org.uk/gridMap/gridMap.jsp?allDs=1&srchSpKey=NBNSYS0000003662) and fascinatingly it is found in almost the same isolated areas as the White Rock-rose. These rare fragmented habitats of dry limestone, with short-grazed south facing aspects have created almost identical conditions for such specialists to cling on to their slopes. However their hold is truly precarious, the species being listed as ‘Near Threatened’ (BRC, 2012). The challenge for the Honewort is made more challenging as it is dioecious (having separate male & female plants, requiring cross-pollination) and has poor seed dispersal, most likely reliant on ants (Carvalheiro, et al., 2008).

These two limestone loving species are literally hanging on in Britain, exposed to human disturbance.  This makes it all the more important to value these wonderful wildlife hotspots and for me to take more care where I lean my tired ‘binocular-ed’ arms.

BRC (2012) Online Atlas of the British and Irish flora [online] http://www.brc.ac.uk/plantatlas/index.php?q=plant/trinia-glauca [Accessed 7/5/12]

Carvalheiro, L.G., Barbosa, E.R.M. and Memmott, J.(2008) Pollinator networks, alien species and the conservation of rare plants: Trinia glauca as a case study. Journal of Applied Ecology, 45: 1419–1427

National Biodiversity Network's Gateway  (NBN) (2012) Grid map of records on the Gateway for Honewort (Trinia glauca) [online] http://www.brc.ac.uk/plantatlas/index.php?q=plant/trinia-glauca [Accessed 7/5/12]

Windless anemones

Over the last few weeks our local Devon woodlands have sprung to life with the white starlight flowers of Wood Anemone (Anemone nemorosa), carpeting the open floors. I’ve also recently been to the beach a couple of times and I have become curious about the marine namesakes, such as the Snakelocks Anemone (Anemonia viridis) pictured above. What is the commonality of the name, ‘anemone’?

Looking up in the dictionary, 'Anemo’ is Greek for wind, which I could have guessed from knowing that an anemometer is an instrument to measure wind. The Shorter Oxford Dictionary (1952) defines ‘Anemone’ as “daughter of the wind” and the Wood Anemone as “the wind-flower”. Other sources state that the wind God, 'Anemos' sent Anemones early to herald his early coming in spring - the Wood Anemone is certainly one of our earliest flowering plants. However there does not seem to be any evidence that wind plays much of a part in the life history of this plant. They spread mainly via underground rhizomes as long-lived clonal groups, and pollination is via insects (Stehlik and Holderegger, 2000). An alternative name is ‘Smell Fox”, which is explained by the musky smell of the leaves (Woodlands.co.uk, 2012) – a bit a blunt and ‘to the point’ of a name, but at least more descriptively accurate.

The link with sea anemones seems more straightforward – these sea creatures resemble flowers with their brightly coloured spreading tentacles – hence the Strawberry Anemone (Actinia fragacea) which is reddish with flecks like pips on a strawberry. Indeed, until modern times many believed that sea anemones were actually plant species. However the resemblance of the large variety of sea anemones does not seem particularly reminiscent of plant anemone species – many look more like colourful sunflowers or daisies.

So, in pedantic summary the anemones don’t have much in common with wind, and sea anemones don’t look any more like anemones than many other flower genera. This should not however stop us admiring the wonderful beauty of anemones, plant or animal.

Onions, C.T (1952) The Shorter Oxford English Dictionary on Historical Principles. Oxford: Clarendon Press

Stehlik, I. and Holderegger, R (2000) Spatial genetic structure and clonal diversity of Anemone nemorosa in late successional deciduous woodlands of Central Europe. Journal of Ecology, 88 (3): 424–435

Woodlands.co.uk (2012) [online] Wood Anemone-  http://www.woodlands.co.uk/blog/woodland-flowers/wood-anemone/  [Accessed 22/04/12]

Painted shells

In nature shells provide varying forms of protection, from snails that use them to shelter their soft bodies from predation and drying out, to bird’s eggs that defend the growing embryo. This week I picked up a discarded egg shell of a Song Thrush (Turdus philomelos), characteristically a stunning summer sky-blue with sparing dark speckles. A couple of weeks ago I was dazzled by brightly coloured Painted Topshells (Calliostoma zizyphinum) dotted about on low tide rocks near Torquay. This led me to wonder at the biological function of some species having such visually distinctive shells that might make them more prone to predation.

Considering the Song Thrush there is some consistency with other birds that make their nests in darkened habitats and pale blue eggs. The Song Thrush chooses either a thick hedgerow, hollow in a creeper, or rarely if on the ground in a shady well-hidden site. It was believed that the distinctive colour may help the adults locate them more easily (Harrison, 1975). Many alternative theories of why thrushes lay blue eggs was summarised by Gotmark (1991): they may be cryptic and provide camouflage by imitating spots of light on green leaves; egg parasites such as cuckoos might have exerted selection pressures historically; the pigmentation of eggs enhances the strength of the egg shell and therefore its resistance to cracking; egg coloration influences egg temperature helping with its regulation. More recent research has tried to test whether the blue-green egg colouration of many bird species provides a health indicator of the female to allow males to modulate their parental investment. However it would appear that researchers are still really none the wiser and so we can only assume that the cost of producing blue pigment is outweighed by some unclear benefit that may no longer be relevant, or that it is simply maladaptive.

The Painted Topshell is the most colourful example of these intertidal molluscs in the UK. The colour varies from yellow or brown to pink or purple and is overlaid with irregular dark purple or red markings. The purplish blotches spiralling around the almost perfect conical shell give the illusion of a spinning top. There is also a white ‘morph’ form which is considered by some to be a separate species. This Topshell is also notable for its frequent shell-wiping behaviour, which would appear to both prevent surface fouling and top up its food intake by as much as a fifth (Holmes, 2001). Despite this interesting colour variation I can find no explanation to its cause. So whilst scientists continue to hypothesise I humbly suggest that we simply sit back and admire nature showing off its surprising beauty.

Gotmark, F. (1991) Blue eggs do not reduce nest predation in the song thrush, Turdus philomelos. Behav Ecol Sociobiol,  30:245-252

Harrison, C (1975) A Field Guide to the Nests, eggs and Nestlings of British & European Birds. London: Collins.

Holmes, S.P., Sturgess, C.J. Cherrill, A. Davies, M.S (2001) Shell wiping in Calliostoma zizyphinum: the use of pedal mucus as a provendering agent and its contribution to daily energetic requirements. Marine Ecology Progress Series, 212:171-181

Spurge-laurel - a healthy pungent purge or scourge?

Very few plants put energy into flowering in the winter due to the cold and lack of sunshine and pollinators. There are some obvious exceptions such as Snowdrops and Winter Aconites. Less obvious is the evergreen shrub, Spurge-laurel (Daphne laureola) which I spotted inadvertently last week in one of our local hedgerows. The origin of the Latin name Daphne apparently comes from the water nymph whom the Gods turned into a laurel-bush to hide from the advances of Apollo (SAPS, 2012). Well in keeping with concealment you would be forgiven for not spotting its flowers, with petals absent and small camouflaged yellow-green sepals. The plant flowers appear from January, a welcome source of nectar for early emergent moths and bees attracted by their strong scent rather than visual cues. But don’t let the sweet fragrance fool you – all parts of a Spurge-laurel plant are poisonous to humans, particularly the bark and berries. It can cause stomach pain, nausea, vomiting, bloody diarrhoea, delirium, collapse and death; even external contact between plant and skin can cause blistering. (Eland, 2012). Some tribes in northern Africa still use a bark extract to poison fish (Eland, 2012). This all serves a useful service for the Spurge-Laurel, as its production of powerful toxic compounds such as coumarin results in a “well defended plant” with very few animals able to eat it (Alonso, 2009).

Interestingly it is not universally toxic to animals; for instance the black berries are eaten by birds like greenfinches without any harm (SAPS, 2012), and in the past used as a veterinary cure for horses (Eland, 2012). It has also been used occasionally in the past for medicinal purposes, such as folk treatments for cancer, toothache and rheumatism (Eland, 2012). Johnson (1856) refers to a “decoction of the root and bark being recommended for children afflicted with worms”, but goes on to warn that “it should never be used, being one of those remedies that can only be employed at the risk of life”. He continues with a more strident note –

“The Lady Bountiful of the village would do more good by confining her benevolent practice to the issue of nourishing food and warm clothing, where necessary, than by trying to combat disease by remedies of which the action is equivocal, if not, as in this instance, dangerous in the highest degree.”

In modern times opinion of Spurge-laurel very much leans towards Mr Johnson’s – well at least botanically rather than his gender insinuations.

Alonso, C., García, I.M, Zapata, N. and Pérez, R.(2009) Variability in the behavioural responses of three generalist herbivores to the most abundant coumarin in Daphne laureola leaves. Entomologia Experimentalis et applicata, 32(1):76-83

Eland, S. (2012) [online] Plant Biographies http://www.plantlives.com/docs/D/Daphne_laureola.pdf  [Accessed 7/03/12]
Johnson, C. (1856) British Poisonous Plants. London: Taylor & Francis.
Science and Plants for Schools (SAPS) (2012) [online] http://www-saps.plantsci.cam.ac.uk/trees/laurels.htm [Accessed 7/03/12]

A Devilish Mis-Tor-y Tour

Over the last few weeks as the weather has turned colder I have felt a compelling draw towards Dartmoor. Most days I glimpse this wild plateau, discrete in the distance; a feint hint of something awesomely ancient, soaked in legend and mystery. Last week we paid a quick visit to the highly accessible Haytor, cloaked in snow and ice. However I yearned for something more remote and wild and so geared up yesterday to do a circular walk around Great Mis Tor on the west side of the moor. Driving to our starting point we crossed an iced and undulating landscape, intermittently crested by tors, the granite outcrops resembling the broken teeth of giants or fossilised horse dung. Mis Tor is aptly named, frequently wrapped in mist as it was yesterday, filling the whole of the Merrivale Valley. Undaunted we trudged up the icy track barely able to see more than a few yards ahead, until quite unexpectedly loomed a huge grotesque visage out of the mist - a contorted ugly witch-like head, featuring a hooked nose, goitre and warts (see image above). This was Little Mis Tor glaring upwards to its more foreboding fellow. It did not take much longer to find Great Mis Tor, or at least its large collar of broken stones. There is apparently a notable rock basin on the peak, Mistorpan or ‘the Devil’s Frying Pan, which has led to “speculation about sacrificial rituals, with blood collected in the basin running out along an [adjacent] groove” (Sale, 2000). There is a more logical geological explanation about natural erosion but don’t let this get in the way of a good story.

Down on the slopes my eye was caught by the striking red of the lichen Devil’s Matchstick (Cladonia floerkeana) (see image below), an apt discovery on this spooky walk. The Cladonia genus of lichens are common on heathlands, enjoying the clean air of such habitats. The name is derived from the Greek ‘’cladon’, meaning branching – these are easy to recognise lichens with their brightly covered fruiting bodies (ascocarps) borne on the top of the podetia (Cladonia Resources, 2012).

As we descended into the Merrivale valley, crossed the rushing brook, and climbed the other side we found ourselves in the middle of a Bronze Age settlement. Standing within the remains of an ancient hut circle we tried to imagine a thriving community looked down on by the imposing tor. Our final mystery lay above this settlement; a stone circle, or at least what remained after past misdemeanours of troops using it as target practice during the Second World War (Sale 2000). By this time the sun had broken through the mist to show us the full breathtaking beauty of an aged landscape decorated by human antiquities; geology merging with mis-tor-y!

Sale, R (2000) Dartmoor – Collins rambler’s guide. London: HarperCollins.

Cladonia Resources (2012) [online] What is Cladonia? http://www.cladonia.co.uk/component/content/article/10.html [Accessed 13/02/12]

Wild tapas from Alexandria

Walking along a local Devon lane last summer I came across a striking black seeded umbel (see image) - An umbel is the flat topped inflorescence, like an upturned umbrella, characteristic of the umbellifers or carrot family. The black colouration, large size (up to 1cm) and angular ridges of these seeds was a good indicator that it was an Alexanders (Smyrnium olusatrum) plant. A sample of this structural plant architecture has contributed to an interesting display in our lounge, embellished at Christmas with a touch of glitter. In the last few weeks I have observing the fresh green growth of the Alexanders celery scented leaves fighting the winter cold in many of the local hedgerows (see image).

Alexanders seems to enjoy the slightly warmer climes of maritime and sub-maritime habitats such as many parts of Devon. It was introduced by the Romans, but now fully naturalised in hedgerows, roadsides and on cliffs. The first written record in Britain was before 1562 when S. olusatrum was recorded “in Ilandes compassed about the se, as in a certain Iland, betwene the far parte of Somerset Shere and Wales” (Turner, 1562; cited in Randall, 2003). Its name possibly derives from the Italian and German denomination, Herba alexandrina having been supposed to have been brought from Alexandria in Egypt (Randall, 2003).

Alexanders was a common pot-herb in kitchen gardens for many centuries, but fell out of favour in modern times. Today’s wild foragers however certainly do not turn up their nose at such a useful plant. Young leaves add a bit of ‘spice’ to salads, but most prized are blanched stems eaten like asparagus with melted butter and a dash of lime juice. For the more culinary adventurous you could try the wild tapas of ‘Spicy Alexanders in Hot Tomato Sauce’ using stems, or ‘Pickled Buds’ with their heavy scented flavour (Harford, 2011). Of course do make sure you are clear about your identification as there are a number of poisonous closely related species!

Harford, R (2011). Eatweeds: Wild Food Recipes (Volume 1)

Randall, R.E. (2003) Smyrnium olusatrum L. Journal of Ecology, 91(2):325-340
Turner, W. (1562) A New Herbal. Pts 2 & 3. Arnold Birckman, London, UK.