I've been very impressed with the New Zealand media's reporting of the Christchurch earthquake. They've managed to balance the need so many of us have felt to understand the terrible tragedy of the 22nd with the victims of that tragedy's right to privacy in such an awful time. Up untill today, they'd also shown great restraint in not indulging in the story Ken Ring, the astrological weather forecaster who claims to have predicted Tuedsday's quake. It seems Campbell live has given in to the temptation, and will feature Ring's 'forecast' today. I have a draft of a post dealing with Ring's claims on the way, but I won't have time to finish that today, so let's make one thing clear.

On his website, Ken Ring has predicted earthquakes for, at least, the 24th of September, the 1st and 7th of October the first week in November, the 20th to the 27th of January, the 1st to the 5th and 19th to the 25th of March and the 17th of April. In fact, in one post, giving him the +/- one day he needs in order to claim he predicted the February 22nd quake , he paints more than half of the year as a time of increased earthquake risk (those are the red circles):

He also predicted a particular pattern of aftershocks on the day following the quake, and, when that failed to happen deleted the failed prediction from his twitter stream (stay classy Ken). And he missed the boxing day aftershock. [note: it's possible Ken didn't delete his prediction for aftershocks on the 23rd, that particular tweet does show up sometimes for some people]

No matter how hard we try, our brains come pre-built to be emphasise "hits" like Ring's prediction and discount the more plentiful "misses". The real question we should ask ourselves when we hear that Ken Ring predicted the Christchurch earthquake is "how likely is that he 'predicted' this event, even if his method doesn't work". By my count, for any earthquake there's about a 50% chance Ring will claim to have predicted it no matter what. I don't think we should be amazed he got this one.

Hopefully I'll have a complete post expanding on this reasoning up by tomorrow.

update: The Campbell Live has just aired, and, boy did they do a good job! Very clearly set Ring apart from the science, but his failures to him and presented the real science of earthquakes. Nice one.

Labels: Ken Ring, sci-blogs, skepticism

I think I've already said that the jumping spiders (family Salticidae) are my absolute favourite group of spiders. As much as I like the Dictynids I've been observing in our agapanthus, if I was asked to pick the group that took the next biggest place in my heart I'd have to go for the crab spiders (family Thomisidae). I've written about these spiders before, so it you want the run down on the biology of these 'sit and wait predators read those posts, today I'm just showing off some photos of a partcularily striking crab spider I found hiding under a banana leaf in Vanuatu:

If you look closely at those enlarged "raptorial" forelegs you can see downward-facing spikes which are used to increase the spider's grip on any creature foolhardy enought to fall within their grasp:

One of the reasons I like jumping spiders so much is they really show no fear when it comes to humans. Most spiders, despite their reputation, will run away when faced with a someone snooping around their hiding place, whereas jumping spiders very clearly eye you up as possible meal. Crab spiders aren't quite so outgoing, but they aren't timid either. This one got fed up with me holding its leaf up to get a photo, and decided instead to attack the camera lens then run up my arm. Whe even that approach didn't keep the camera out if its face I got a very clear threat signal:

One day I going to run a whole set of out of focus photos of bugs attempting to attack my camera, but for now I have other work to do!

Labels: citizen science, crab spider, photos, sci-blogs, sunday spinelessness, Thomisidae

Like many New Zelanders, I'm struggling to understand what happened yesterday. We all know that a devestating earthquake struck Christchurch around lunchtime yesterday, killing at least 75 people and destroying much of that beautiful city. Of course, the tragedy of the Christchurch earthquake can be measured only in the lives it's affected, you don't need to know about rocks to understand this story, which has no doubt been repeated in a thousand different variations across the city. Obviously, the most important thing at the moment is that people in Christchurch get the help they need. Still, if you have a brain like mine, then somewhere in the struggle to understand the tragedy and the overwhelming feeling of uselessness you just need to know how this happened. I'm going to use this post to collate links to articles that do a good job of explaining some of the science behind yesterday's earthquake, but first here's what I've learned from reading them.

The quake seems to part of the sequence of aftershocks from the 7.1 Darfield earthquake of September. It might be that the massive release of pressure in that quake added to the strain at a fault that was already under stress; or it might simply by part of the pattern of aftershocks following that quake which have been progessively more shallow as they've proceeded. What's abundantly clear is that, even though this new quake was 6.3M and therefore about 5 times less intense than the Darfield one at its origin, it was much more violent than the first. The eipcentre was only 5km for the centre of the city and only 5km below the surface. The peak acceleration, one measure of the strength of the shaking from a quake was 1.88 g which is about 50% stronger than any measurement from the Darfield quake and much greater than anything recorded near to the city in that event. That powerful shaking, the lunchtime rush and already damaged buildings proved to be a terrible combination.

GNS

• Christchurch badly damaged by magnitude 6.3 earthquake
• "Shake map" for most recent quake
• Rolling updates of latest aftershocks
• Full details of Darfield Earthquake

Science Media Centre

• Experts on major quake near Christchurch
• Timing of quake, weakened buildings – major contributors to loss of life
• Engineering expert on 6.3M Christchurch earthquake
• The quake: Experts on psychological impact, building engineering, geology

Blogs/News/Whatever

• Chris Rowan at Highly Allochthonous
• Sci-Am interview with Robert Yeats
• ABC science with comments from Trevor Allen
• The Daily Telegraph has comments from Gary Gibson
• NZPA reporting from Tuesday
• Hamish Campbell in the Herald
• Anna Sandiford at Forensic Scientist on the grim task of identifying bodies
• The Herald on first aerial survey looking for the fault
• New Scientist report with comments from many New Zealand geologists
• Hamish Campbell says seismic waves may have rebounded from hard basalt under the Port Hills
• Robert Yeats again talking about need to map more faults to asses quake risk (think this will be major discussion point was the clean up is done)

Labels: earthquake, sci-blogs

I'm not finished with photos of spineless life from Vanuatu just yet, but I do have to interrupt that stream of posts again thanks to goings on in our backyard. Ever since I started writing this blog I've wanted to shoehorn a quote from James Thurber, and on Friday I had an encounter that gave me the chance. So here goes:

Surely nothing in the astonishing scheme of life can have nonplussed Nature so much as the fact that none of the females of any of the species she created really cared very much for the male, as such. For the past ten million years Nature has been busily inventing ways to make the male attractive to the female but the whole business of courtship, from the marine annelids up to man, still lumbers heavily along, like a complicated musical comedy. I have been reading the sad and absorbing story in in Volume 6 (Cole to Dama) of the Encyclopædia Britannica. In this volume you can learn all about cricket, cotton, costume designing, crocodiles, crown jewels and Coleridge, but none of these subjects is so interesting as the Courtship of Animals, which recounts the sorrowful lengths to which all males must to go arouse the interest of a lady.

After that memorable introduction, Thurber lists some of the absurd behaviours that males of various species resort to in their attempts to get the attention of females. The fiddler crab's odd little dance, the bowerbird's colourful treasury and the nuptiual gifts providied by some tree crickets are all covered. Thruber restricted himself to the behaviour of animals in his essay, but the pursuit of love has also wrought some very strange body modifications. The peacock flashes his fabulous tail in the hope of winning a peahen's heart, in certain deep-sea fish the male lives only to find a female to which he might attach himself, so he can be subsumed into her body and then there is the creature that ran out from under our recycling bin on Friday:

Those impossibly long and skinny legs mark him out as a harvestman (a group related to spiders) from the sub-order Palpatores. Once I'd prevented his escape, and taken a few more photos I shot an email off to Christopher Taylor who, as well as writing Catalogue of Organisms, just happens to be the brains behind the most recent taxonomic review of these harvestmen in New Zealand. Chris was kind enough to identify him, so I can tell you that you're looking at Pantopsalis albipalpis. Ordinarily an animal that appears to have crawled out of the pages of The War of the Worlds would be more than enough for a post here, but those spindly legs are as nothing when you compare them to the crane-like appendages growing from his head.

Amazingly, those are his jaws, or at least his chelicerae. Arachnids have two sets of limbs associated with their heads, the pedipalps (which spiders use almost like legs, and, in males to deliver sperm if you can imagine such a dual-purpose organ) and the chelicerae which are used to grasp prey and direct it toward the mouth (arachnids don't have chewing mouth-parts like many other arthropods).

Females from Pantopsalis and the related genus Megalopsalis have more or less normal chelicerae which point downwards, let their owners shuffle food towards their mouth and do very little else. As you can see, males are built a little differently. In fact, those massive hinged jaws are so different than the female form that males and females have frequently been mistaken for different species. Even within males, several species have two distinct forms; one with relatively low abd broad chelicerae and another with tall slender chompers.

It's not entirely clear what purpose such massive chilicerae serve, but the fact they are limited to males makes it a pretty sure bet they're just another example of the what Thurber called "the mournful burdens of the male" in the biological world. Perhaps female Pantopsalis just go mad for a giant chelicera, and in each new generation males have to sport ever more rediculous dentition if they want to turn a girls head. The mean spikes and nasty looking claws seem to suggest the giant chelicerae are more of a help to fighters than lovers. A few distantly related harvestman groups have also evovled overgrown jaws, and in those species the males fight with each other for the chance to mate. As with so much of New Zealand's invertebrate fauna, no one has ever studied our harvestmen in a behavioural or ecological sense. It would be fascinating to understand the forces that created this out-sized morphology, and how the distinct male forms are maintained (do they relate to different fighting strategies?) but until someone studies them in detail we just can't know.

However they got their giant jaws, I can't look into the eyes of this last photo without thinking this particular harvestman shares a little of Thurber's opinion on the lengths to which Nature's male have to go:

There are quite a few places you can find better pictures of New Zealand harvestmen around the web. Alan from half-pie has a Megalopsalis, Sciblogs own Brenden Moyle has photos of distantly related harvestmen that have normal sized chelicerae but massive pedipalps and TERRAIN, a forest restoration project in the Taranaki, has some great details of the claws.

The quote at the start is from Thurber's story Courtship Through the Ages which was published in the New Yorker then a collection of short stories. It's really very funny.

Christopher's paper on New Zealand's Pantopsalis is

Taylor, C., 2004. New Zealand harvestmen of the subfamily Megalopsalidinae (Opiliones: Monoscutidae)–the genus Pantopsalis. Tuhinga, 15, pp.53-76.

Labels: harvestman, Opiliones, photos, sci-blogs, sexual selection, sunday spinelessness

Recently, there's been a little bit of talk among science bloggers about the need to murder your darlings. Christe, Carl and Ed are talking about excising some of your favourite passages of writing in order to let a whole post hold together, but I've been thinking about the phrase in a different context recently. I'm an invertebrate evangelist, and I utterly fail to understand how most people manage to package all the world's invertebrates into one giant and creepy category. But no matter how much you love bugs, you have admit some of them are just pests that need to be dealt with.

Lately our garden has been taken over by wasps. That's "wasp" in the every day sense in New Zealand, the murderous little yellow and black flying insects; we have thousands of native wasp species but they are all solitary and most are small and limited to native bush, so they don't really enter our consciousness. The German Wasp and its cousin the Common wasp (Vespula germanica and V. vulgaris), are something quite different. They are both social insects that build nests that support thousands of workers, each of which lives to bring up their queen's brood. Unlike honey bees and bumblebees, where the workers collect nectar and pollen to feed their young, wasp larvae need flesh. In late spring, the first generation of workers leave the nest and start collecting insects (especially caterpillars it seems) to feed to the developing larvae. The adults feed on nectar, but in the start of the season they are mainly sustained by a sugary substance the larvae produce in return for their food. In the middle of summer adults spend more time looking for their own food outside the nest, and that's why we start noticing them around fallen fruit and picnics come December or so.

There is nothing quite like these introduced wasps in the New Zealand fauna. The relative nativity of our insects, the lack of any predators and our relatively warm winters (which don't kill-off the nests every year) mean these wasps live at much greater densites in New Zealand than they do in Europe. In native beech forest, especially sourthern forests that produce honeydew thanks to native scale insects, there can be as many as ten thousand workers in one hectare, that's one wasp for every square metre of forest. In beech forests in particular, wasps are a complete disaster. They can wipe the forest floor clean of native insects and spiders and monopolise the honeydew, which is an important source of energy for native birds. Indeed, if you were to weigh all the wasps in some sections of native forests it would add up to more than the combined weight of all the native birds. In urban and rural settings wasps are a pain (literally, I was stung by one as a child and remember it well).

So, as opposed to almost every other invertebrate that crosses my path, when I see an introduced wasp I get just a little sense of revulsion. When i tracked down the the source of our graden's yellow and black plague to two different nests on our property I hardly thought twice before I bought a bottle of carbaryl to deal to them. The first nest was no problem, it was dug into our clay bank and had a nice clear entrance site that I could sneak up to at night - letting me cover the entrance with the poisoned powder. The other nest was tougher.The entrance to that one was obscured in amongst a compost pile, right next to some weedy flowers which are visited by honey, bumble and and even native bees. Carbaryl is a broad-spectrum insecticide, and bees are having a hard enough time without being caught in the crossfire of this war, so a scorched earth policy wasn't really an option. Instead, I got a long sleeved shirt* and a spade and began to excavate the entrance to the nest. This process basically involved me clearing away a little of obscuring material before dropping the spade as a bolt of WHITE-HOT ADRENALINE passed through my body as a single wasp flew in roughly my direction for a little while. Quite a few rounds of this process ended when the last blow of my spade revealed not the entrance to the nest, but the very middle of it.

I'd cut a wall of the nest open and revealed a swarming yellow and black mass of wasps (who were more interested in attacking the spade than me) and the cells they'd constructed to house their young. Once the initial buzz had died down, I managed to extract the section of the nest that I'd dismantled and in doing so I learned something. Wasps might murderous, stinging invasive pests, but they're also quite beautiful. In all the time I'd been cursing their presence in my garden, they'd built an incredible piece of architecture out of the weeds we'd thrown away. My photos hardly do their efforts justice, but you get an idea.

A section of the wasp nest with the major stages of development (eggs, larvae and pupae) on display

One of the very few spineless creatures that I thought had no place in my heart had really amazed me. Beautiful as their creation might have been, they are still a pest and later that evening I came back to their now exposed nest and killed them, but it was a much more difficult job than the first nest.

*Really. I don't know what sort of protection I though this was going to offer...

If you want more posts dealing with ravenous hordes of social insects, Alex Wild at Mrymecos declared last week "Army Ant Week" and celebrated by producing some of the most wonderful photographs and interesting posts you're likely to find.

Labels: environment and ecology, photos, sci-blogs, sunday spinelessness, wasp

Time for another tropical beetle from Vanuatu, and what could be more charming than a ladybird*?

Or its absurdy spikey larvae?

This ladybird is probably a bit larger, a bit rounder and a bit oranger than the ones you are used to seeing in your garden. The more familiar ladybirds are more that just a pretty set of elytra, they're a force for good. Both the larvae and the adults of most of the familiar red and black ladybirds eat aphids, so having a few around in your garden saves on insecticide:

Ladybird larvae 'controlling' aphids, thanks to Gilles San Martin for making this image CC 2.0

The big orange ladybird in that first photo is not nearly so helpful. It's Henosepilachna vigintioctopunctata**, commonly known as the 28 spotted ladybird or the hadda beetle. The hadda beetle is a major agricultural best, because both the adult and larval stages are herbivorous and have a patricular liking plants of the family Solanaceae. That means potatoes, tomatoes, eggplants and (worst of all?) chilies can have their leaves skeletonised by beetles, and a beetle infestation can reduce a year's crop by up to 25% if not controlled.

You might note that this is the third post I've written about invertebrates from Vanuatu, and it's the third time I've written about an introduced pest. That's not by chance. Islands are hugely interesting for evolutionary biologists, but human introductions have seriously changed island ecosystems.

Take another look at that chewed-over leaf. Now imagine that each of those small white sections to the left of the photograph is a brand new island in a green ocean. In almost no time at all, winds would carry seeds to our little archipelago and life would start to claim the bare rocks. But we don't know which plants would make it. Dispersal and colonisation are random events, each island would collect its own subset of the seeds drifting past , and so start to develop its own flora. Once those plants have taken hold, the rain of wayward and drifting insects (and even snails) that fall everywhere on earth would have a chance to establish themselves. Again, the isolation of our islands means different species will fall on each one, and different ecological relationships will start to form. Our islands might survive for 20 million years before they're reclaimed by the sea, and in that time the unique beginnings of each island's ecosystem will mean a different evolutionary history will play out. In this way islands are evolutionary experiments, and island ecosystems have given risr to some of evolution's weirdest creations - isolation from the mainland has let iguanas become marine animals, finches become vampires and pigeons give up on flying.

But islands are no longer isolated from the rest of the world. The hadda beetle is probably native to Russia and, without humans moving plants around, would never have had a chance of making it to a Pacific islands. Now it lives in almost all the way across the tropical Pacific (here's a terrible photo of one I took in Rarotonga, 3000km away from Vanuatu):

In fact, there is an entire "tramp" assemblage including, but hardly limited to, big-headed ants, mynas, land snails, centipedes, paper wasps and mile-a-minute weed that can be found almost everywhere you find people in the tropical Pacific. These Pacific-wide introductions have pushed out native species, and together they have replaced some of evolutions most exuberant expressions with a bland mono-culture. The problem is not quite as bad as it might seem. The tramp species are mainly moved about by commerce, so many of the introduced species are associated with agriculture or at least lowland environments. In most islands, as you climb higher you find a more 'native' flora and fauna (for instance, all the partulid species left in the Society Islands are restricted to mountain tops).

By the way, the hadda beetle's bid for world domination continues: last year it was recorded in New Zealand for the first time. It's known to have set up shop in Auckland, but if you find hadda beetles somewhere else MAF might want to know about the invasion's spread.

*That's "ladybug" in American English, coccinellid or "lady beetle" among scientists and "ngoikura" in Māori

** That name might seem like a mouthful, but the species epithet at least makes sense, viginti-octo-punctatameans "twenty-eight-spotted". Most ladybird species names follow this rule

Labels: beetle, coccinellidae, Cook Islands, environment and ecology, island biogeography, photos, sci-blogs, snails, sunday spinelessness, vanuatu