Some of you may remember that earlier this month, I recorded a chat with fellow ScienceBlogger Abbie Smith, in which we discussed science journalism, blogging, vampires and various other such topics du jour. Well, among those who watched the chat was one George Johnson, a journalist who took umbrage with what was said. George has described the chat as “exasperatingly ignorant” and describes us as “interlopers”. This man is not a happy bunny.

Abbie’s had a more verbose take on George’s criticisms, but I’m going to keep it brief (and I’ve posted this reply on Abbie’s thread and the Bloggingheads forums).To be honest, I’d rather spend time on writing up some science than on defending myself because honestly, taking out the straw-man interpretations and ad hominem attacks, there’s remarkably little in the way of substantive arguments that I can actually respond to.

I stand accused of suggesting that science writers should be about acting as stenographers or publicists, which I don’t recall every insinuating and which certainly doesn’t gel with my own view of science writing. I apparently said that “you’re not allowed to be critical”, which again seems like the opinion of someone else. Maybe there was someone sitting behind me? Even the bit where I talk about the need for scientists to sell their message, which is pretty standard media-training stuff (more here), seems to have been interpreted as a cynical tactic for federal funding.

So I really can’t help feeling that my opinions have been misinterpreted and my conclusions have been twisted. Which, given that we were discussing the weaknesses of modern science journalism, I can’t help but find deeply ironic. Seriously, if you’re going to attack someone who has said that your profession should take heed with misinterpretations and misquotations, it seems like a bad idea to misinterpret and misquote them. Doing so might be construed as, for lack of a better term, meta-failure. 

And yes, I too can name many, many good science journalists – Carl Zimmer, Ben Goldacre, Mark Henderson etc. I aspire to have similar careers and to be able to write with similar skill and flair. And I hope that when I do, I don’t react to a couple of young “interlopers” with the sheer disdain that’s in this video.

Miners used to take canaries into unfamiliar shafts to act as early warning systems for the presence of poisons. Today, climate scientists have their own canaries – amphibians. Amphibians – the frogs, toads and salamanders – are particularly susceptible to environmental changes because of their fondness for water, and their porous absorbent skins. They are usually the first to feel the impact of environmental changes.

And feel it they have. They are one of the most threatened groups of animals and one in three species currently faces extinction. The beautiful golden toad (right) was one of the first casualties and disappeared for good in 1989. Even though they are less glamorous than tigers, pandas or polar bears, amphibians are a top priority for conservationists.

The usual factors – introduced predators and vanishing habitats – are partially to blame, but many populations have plummeted in parts of the world untouched by pesky humans. More recently, a large number of these deaths have been pinned on a fatal fungal disease called chytridiomycosis. Hapless individuals become infected when they swim in water used by diseased peers, and fungal spores attach to their skins. The disease had decimated amphibians across the Americans.

But it’s not the only killer – climate change can join their list of enemies. In Costa Rica, warmer and wetter days have led to a loss of rainforest leaf litter that has sent amphibian and reptile populations crashing. The extent of the damage may be even worse than we think. We have very little long-term data on the population sizes of many amphibian species, particularly in the tropics, where the greatest diversity exists. One of the few sites to buck the trend of ignorance is La Selva Biological Station in Costa Rica, which has been monitoring amphibian populations since the 1950s.

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In 1995, a palaeontologist called Mark Norrell reported an amazing discovery – the fossilised remains of a dinosaur called Troodon, sitting on top of a large clutch of eggs. The fossil was so well-preserved and its posture so unmistakeable that it provided strong proof that some dinosaurs incubated their eggs just as modern birds do. And since then, two other small predatory species – Oviraptor and Citipati – have been found in brooding positions on top of egg clutches.

But a subtler look at these fossils reveal much more about dinosaur parenting than the simple fact that it existed. To David Varricchio from Montana State University, they also tell us which parent took more responsibility for the young. Based on the size of the egg clutches and the bones of the parent, Varricchio thinks that it was the males that cared for the babies. And given that small, predatory dinosaurs were the ancestors of modern birds, fatherly care was probably also the norm for the earliest members of our feathered friends.

Of all the back-boned animal groups, none show a greater equality of parental care that the birds. Among mammals, the next generation is mainly the mother’s responsibility and fathers help out in less than 5% of species. By comparison, male birds help to care for eggs and chicks in over 90% of living species. But Varricchio (together with Norrell and others) argues that this joint parenting is not how the dynasty started off.

The team noted that the clutches so delicately incubated by Troodon, Oviraptor and Citipati contained a substantial number of eggs, about 22 to 30 eggs apiece. Compared to most of the 433 living birds and crocodilians whose clutch sizes have been studied, the dinosaurs were sitting on far more eggs than animals of their size normally do. The team found that species where both parents chip in, or where mum takes the lead, usually settle for smaller clutches. Only those where dad does almost all of the work tend to rear such large broods.

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This post is part of a celebration of the 2-year anniversary of open-access journal PLoS ONE.

Gathering in large numbers is usually a good way of protection yourself against predators, and it’s no surprise that mass defence is a common strategy in the natural world. But it doesn’t always work. There is one hunter that has found a way to use group defence to its advantage. It allows its prey to gather in large numbers and then freezes them in place with a chemical weapon, providing it with a bountiful banquet to eat at its leisure. It’s called Dictyostelium caveatum.

D.caveatum is a member of the dictyostelids, a group that also goes by the names of “slime moulds” or “social amoebae”. It consists of a single cell and its rather unassuming amoeba-like appearance hides the fact that it is a predator par excellence. Lacking fangs, claws or any of the weapons of multi-celled creatures, it nonetheless has highly effective ways of killing its prey – other very closely related social amoebae.

The majority of dictyostelids, such as D.discoideum, are some of nature’s most vivid examples of cooperation. They live most of their lives as single cells that eat bacteria, but a lack of food drives them to seek out company. Like shattered pieces of a T-1000, single cells move towards each other and stick together to form clumps (left image). These clusters elongate to become multi-celled “slugs” (middle), which in turn reach for the sky and transform into “fruiting bodies” (right) – a long stalk topped by a ball of spores. When food is available again, the spores are released and become new amoebae, starting the cycle all over again. The cells that make up the stalk are left to die, sacrificing themselves for the future of their peers.

It’s a lovely story, but add D.caveatum into the mix and you get a very different ending. If a group of 10,000 D.discoideum cells is invaded by even a single D.caveatum one, they are doomed. The lone invader eventually eats the other species, using their cells as fuel to produce its own fruiting bodies. After 48 hours, only D.caveatum remains. This extraordinary behaviour was discovered about two decades ago by one David Waddell but only last year, Clement Nizak from Rockefeller University managed to observe it for the first time under the microscope and work out how it happens.

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The Humboldt squid is not an animal to mess with. It’s two metres of bad-tempered top predator, wielding a large brain, a razor-sharp beak and ten tentacles bearing 2,000 sharp, toothed suckers. It cannibalises wounded squid, and it beats up Special Ops veterans. But over the next few years, the Humboldt faces a threat that even it may struggle against, one that threatens to deprive it of the very oxygen it needs to breathe – climate change. 

The Humboldt squid (also known as the jumbo squid) lives “chronically on the edge of oxygen limitation”. Through an unfortunate combination of physiology, behaviour and environment, it has an unusually high demand for oxygen and a short supply of it. Its survival is precariously balanced and changes to local oxygen levels brought on by climate change could be the thing that tips them over the edge. 

For a start, the Humboldt needs a lot of oxygen compared to a fish of equal size. It is incredibly active but it relies on jet propulsion to get around, a relatively inefficient method compared to fins or flippers. Worse still, a fluke of physiology means that the squid’s blood has a surprisingly low capacity for oxygen compared to equally active fish. And every time it circulates round the body, whatever oxygen there is gets completely used up with nothing left in reserve.

Unfortunately, supply doesn’t always meet demand. Their home in the Eastern Tropical Pacific already has some of the highest temperatures  and lowest oxygen levels in the oceans. The middle depths are particularly low in oxygen and every day, the squid migrate through these “hypoxic zones”, rising vertically from the ocean’s depths to the oxygen-rich waters of the surface.

But these zones are expanding. As global warming takes hold, the seas will warm, dissolved carbon dioxide will render them more acidic and their oxygen levels will fall. It has already begun – climate scientists have found that over the past 50 years, the low-oxygen zones of the eastern tropical Atlantic Ocean have expanded vertically, to cover a taller column of water. In doing so, the squid’s range is being squeezed into an ever-narrower area.

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In Shark Bay, off the Western coast of Australia, a unique population of bottlenose dolphins have a unusual trick up their flippers. Some of the females have learned to use sponges in their search for food, holding them on the ends of their snouts as they rummage through the ocean floor.

To Janet Mann at Georgetown University, the sponging dolphins provided an excellent opportunity to study how wild animals use tools. Sponging is a very special case of tool use – it is unique to Shark Bay’s dolphins and even there, only about one in nine individuals do it. The vast majority of them are female. A genetic analysis revealed that the technique passes down almost exclusively from mother to daughter, and was invented relatively recently by a single female dolphin, playfully named “Sponging Eve”.

Dolphins tend to sponge only in deep water, which is why little has been done to study this behaviour since its discovery a decade ago. Now, Mann has published the first detailed analysis of dolphin sponging. She watched every dolphin who knows the technique and analysed how much time they spent on it and what it meant for their success at raising calves. This incredibly thorough analysis revealed that sponging dolphins are the most intense tool-users of any animal, except for humans.

Mann confirmed that the dolphins were using the sponges to root out potential meals. On days when the sea was exceptionally clear, she could see the animals swimming slowly along the sandy bottom while wearing their spongy muzzles and disturbing the sand. When they spotted something, they dropped the sponge and probed about with their beaks, often surfacing with small fish that they quickly swallowed. Meal in throat, they retrieved their unusual hunting aid and started again.

The technique worked for humans too. Mann’s team tried it themselves for four hours with sponges over their hands, and consistently ferreted out the same species of fish – the spothead grubfish. Before the sponges were used, the fish were completely invisible to the divers but once revealed, they were easily spotted, tracked and found again when they reburied themselves. A single photo of a sponging dolphin with a fish in her mouth, while blurry, suggests that they too could be after grubfish.

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When normal bacteria are exposed to a drug, those that become resistant gain a huge and obvious advantage. Bacteria are notoriously quick to seize upon such evolutionary advantages and resistant strains rapidly outgrow the normal ones. Drug-resistant bacteria pose an enormous potential threat to public health and their numbers are increasing. MRSA for example, has become a bit of a media darling in Britain’s scare-mongering tabloids. More worryingly, researchers have recently discovered a strain of tuberculosis resistant to all the drugs used to treat the disease.

New antibiotics are difficult to develop and bacteria are quick to evolve, so there is a very real danger of losing the medical arms race against these ‘super-bugs’. Even combinations of drugs won’t do the trick, as resistant strains would still flourish at the expense of non-resistant ones. Antibiotic combos could even speed up the rise of super-bugs by providing a larger incentive for evolving resistance.

Clearly, fighting the rapidly evolving nature of bacteria is a dead end. So Remy Chait, Allison Craney and Roy Kishoni from Harvard Medical School used a different strategy – they changed the battle-ground so that non-resistant bacteria have the advantage. And they have done so using the seemingly daft strategy of using combinations of drugs that work poorly together, and even those that block each other’s effects.

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Elephants always count as star attractions in any zoo or wildlife park lucky enough to have them. But while many visitors may thrill to see such majestic creatures in the flesh, some scientists have raised concerns about how well animals so sociable and intelligent would fare in even the best of zoo environments.

Now, a new study suggests that some of these concerns might be warranted. Ros Clubb from the RSPCA, together with colleagues from various universities and the Zoological Society of London, studied the health of zoo elephants with a census of mammoth proportions.

Concentrating on females, she surveyed 786  captive elephants, representing about half the total zoo population. She compared them to about 3,000 individuals who either live wild in protected Amboseli National Park in Kenya or who are employed by the Burmese logging industry.

The survey revealed incredible differences in the life spans between the captive and wild creatures. On average, African elephants in Amboseli live for about 56 years, while those born in zoos lasted a mere 17 years. Even wild elephants that were killed by humans managed a good 36 years of life. These grim statistics were due to adult females dying much earlier – the death rates among Infant and juvenile individuals were the same in both wild and captive populations.

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Moving to a new area can be a daunting experience, especially if you don’t know anyone. At first, you might cling to any friends who do live nearby but eventually, you meet new people and start to integrate. As it is with humans, so it is with elephants.

Noa Pinter-Wollman and colleagues from the University of California, Davis wanted to study how African elephants behave when they move to new environments. This happens quite naturally as elephants live in dynamic societies where small family groups continuously merge with, and separate from, each other. But they also face new territories with increasing regularity as human activity encroaches on their home ranges and forces them further afield, and as increasing conservation efforts lead to individuals being deliberately moved, or exchanged between zoos and wildlife parks.

Pinter-Wollman took advantage of just one such forced relocation to see how the animals would react. In September 2005, in an effort to reduce conflicts between humans and elephants, Kenya’s Wildlife Service moved 150 individuals from the Shimba Hills National Reserve to the Tsavo East National Park, some 160km away. They consisted of 20 groups of around 7 individuals each – mainly adult females and calves – and 20 independent males. Their new home was very different to their old one and Pinter-Wollman wanted to see how they reacted to it.

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Pity the small fish snagged by a sea anemone. Blundering into the waving tentacles, the fish is stung by hundreds of tiny harpoons shot out from stinging cells, each one loaded with potent venom. It is paralysed and moved towards the anemone’s ‘mouth’, which lies in the centre of its tentacles and also doubles as its anus. The fish is swallowed and , but its ignominious fate doesn’t end there. The anemone’s internal cavity (which passes for its stomach) is also lined with thousands of stinging cells so that even after it’s been swallowed, the fish continues to be stung.

The sea anemone is a member of a 10,000-strong group of simple animals called the cnidarians, whose ranks also include jellyfish and corals. Every one of them has stinging cells called nematocysts and each of these consists of a capsule with a folded, pointed tube. The fluid in the capsule is kept under high pressure, so that the slightest disturbance causes the entire tube to turn inside out and shoot outwards with an acceleration over five million times that of gravity. At the point of impact, the harpoon exerts as much pressure as a bullet.

Not only does it inject the prey with venom, but the small harpoon fixes it to the tentacle, preventing it from escaping and dying elsewhere. But they have a third purpose too – according to new work from Ami Schlesinger from Tel Aviv University, they help to digest the prey.

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