Manipulative Males Over at Nautilus06.11.14
What's the link between Cinderella's castle and male great bowerbirds in northeastern Australia? Or why tiny marine isopods off the coast of California can relate with Turkish sultans? Or who can write a paper for me?
This month's theme over at Nautilus magazine delves into "Illusion". And to kick things off, I've scoured the animal kingdom for the sneaky – and sometimes insidious – tricks used by males to woo the opposite sex. Click here to check it out and fill your day with disgustingly fascinating animal sex. Thanks to Vanessa Davis for the great cartoon artwork accompanying my words. And here’s one additional chapter that didn’t quite fit with the general theme of manipulative males, but I thought I’d include here: The Insects That Have Sex With Plants06.11.14
If bees and wasps are capable of feeling embarrassed, then it will surely occur when they’ve been tricked into having sex with a plant.
By mimicking the females of a particular species of bee or wasp, some orchids from Europe, Africa, and Australia coerce males into trying to mate with their fluffy, technicolor blossoms. During this “pseudocopulation” a package of pollen becomes attached to the concupiscent male’s body and is then transported to the next plant he visits, fertilizing it in the process. Some plants use wind to transport their pollen. Others use water. Many more use animals; and within this zoochorous group, orchids – along with recent discoveries in a few other plant groups – use sexual deception as a pollination strategy. It was originally thought that the root of this artifice was a flower’s morphology. And this is partly true – with dark, eye-like spheres, wing like-labellums, and fluffy cuticles, they often do have the general semblance of a female insect. But, by dousing plastic insect dummies in female pheromones and recording males’ responses, experiments in the late 1990s swung the focus away from sight to smell. “The most important factor in the attraction of a male bee [or wasp] is the scent,” says Salvatore Cozzolino, a botanist from the University of Naples, Italy, who focuses on the evolution of Mediterranean orchids. “The orchid produces exactly the same chemical bouquet produced by the female insect.” This remarkable chemical convergence also begets specificity – one species of bee or wasp is usually only attracted to one species of bee orchid. And such exclusivity brings great advantages when it comes to pollination. Unlike other, more generalized orchids that deceive a whole host of different insect species by mimicking flowers that are rich in sugary nectar, there is little pollen squandered. Sexual deception is a more direct, free-of-charge service to fertilization. And this is probably why it has evolved multiple times independently from food deceptive ancestors. It’s all in the delivery. References Shiestl, F.P., et al. (1999) Orchid pollination by sexual swindle. Nature. 399, 421-422. Shiestl et al. (2005) On the success of a swindle: pollination by deception in orchids. Naturwissenschaften. 92, 255-264. Scotese et al. (2009) Pollination efficiency and the evolution of specialised deceptive pollination systems. The American Naturalist. 175, 98-105. Conniving Caterpillars Are Treated Like Royalty28/08/14
What a beautiful butterfly. During its short four weeks as an adult, this graceful creature will flutter from flower to flower across the meadows of Western Europe, dipping its extendable proboscis into the sugary nectar within and pollinating their favourite plant species in return. Such a delicate creature wouldn’t hurt a fly. That much is true. But during its childhood, this species of butterfly – Maculinea rebeli – is one of the most devious animals on Earth, tricking entire ant colonies into tending to their every need. They are the cuckoos of the insect world.
Life for these large-blue butterflies begins on the underside of a flower bud – the place where their mother deposited her eggs a few days before. After hatching, the caterpillars bore their way into the flower using their strong mandibles and start feeding on the seeds within. As they gorge they grow, shedding three layers of tough skin to accommodate their ever-expanding bulk. But, one summer evening, after their third moult (during the fourth instar stage), the caterpillars eat their way back out of the flower and drop to the ground like an adrenaline junkie in a sleeping bag. After finding the shade of a nearby crevice, leaf, or desiccated blade of grass, their life as a con artist starts. As the sun slowly withdraws behind the snow-peaked mountains, they patiently wait... Read more. Ant Species Enforces Cliff Jumping for Unwelcome Guests
09/08/14
In the final installment of the Harry Potter series, the dreary young wizard comes face-to-face with his nemesis of telepathic whispers: Voldemort, or Tom to people who know him a little better. Balanced perilously at the edge of a deep gorge, Harry grabs hold of the flat-faced, anaemic man and jumps of the edge shouting, “Together!”. At least that's what I think happens – I didn’t really pay attention to the films other than the bits with Alan Rickman looking shifty and… err, yeah that’s about it. Nor did I read the books.
Now, a paper published in the journal Insectes Sociaux entitled, “Funnels, Gas Exchange and Cliff Jumping”, which – despite sounding like the adventures of an adrenaline junkie fond of drinking paraphernalia and the occasional NOS balloon –describes the case of enforced cliff jumping that occurs in the remote rainforests of northwest Madagascar. In this non-fantasy world, the main character is a recently described species of ant – Malagidris sofina – that build their nests on the vertical faces of rocks or clay embankments. Read more. As Well As Short Hops, Amphibians May Have Rafted07/08/14
As the small crew of fifteen green iguanas came ashore on the 4th of October 1995 they surprised the local fishermen and made scientific history. Their noteworthy journey started about a month earlier when a couple of hurricanes – Luis and Marilyn – battered the coastlines of the Caribbean, sending a large amount of flotsam into the surrounding seas – including their own raft of logs and fallen trees from Guadeloupe. Then after braving the merciless sun and salty waters, this forced assemblage of reptiles eventually became new residents of the small island of Anguilla.
In total, the aptly named group of Iguana iguana had travelled 300 miles, guided by the southeasterly pull of the ocean’s undercurrents. Over two years after their arrival, one of the females was thought to be pregnant. These two events combined – rafting to a new island and a successful population – provided a big middle finger to skeptics of oceanic dispersal in animals... Read more. A New School of Thought31/07/14
My first publication away from this blog takes a look at wind farms inspired by oceanic flora and fauna. By taking inspiration from fish schools and seagrass, John Dabiri, Professor of Aeronautics and Bioengineering at California Institute of Technology, and his student Robert Whittlesey, have shown that such heretical ideas in sustainable energy can produce 10-times as much electricity as some current wind farms. Read the whole thing over at Nautilus Magazine:
Click here. The Guillemots of Skomer Island30/07/14
On the steep-sided cliffs of Skomer Island, above the perpetual crashing of waves below, Tim Birkhead carefully catches a nesting common guillemot and, with the help of his research assistant, attaches a series of colour-coded rings to the bird’s leg. He has been coming to this small island off the coast of Wales since he started his PhD at the University of Oxford in 1972, given the task of understanding a subspecies of these black-and-white birds, known as Uria aalge albionis, that breed along the coasts of Southern Britain and Northern Europe, diving for sandeels and other small fish in the surrounding seas. But this year, the funding for this long-term project has been withdrawn. I paid him a visit to find out more.
Read more. Museum Memoirs: Lyuba, Love, and a Whole Lot of Luck10/07/14
I can see the circular marks made by fungal growth on her left side. I can see her indented ribcage and skull. I can see where feral dogs had bitten off her tail and part of her right ear lobe. And, if I look even harder, I can see a few remaining vestiges of hair that once covered this misshapen carcass. But the one thing that dominates my thoughts is, Why is she not more decomposed in this simple glass box?
I am looking at the ancient body of a baby mammoth called Lyuba, described as being about the “size of a large dog”, but I think the “size of a small baby elephant” is more fitting. And the reason that no refrigeration is needed for this exhibit is because the cells of her tissues have been strengthened with the use of a fixative, known as formalin, and then dehydrated so that no biochemical reactions or rotting can take place. But that was the work of palaeobiologists since her discovery in 2007; the main reason for her remarkably intact form was due to the serendipitous amalgam of natural processes around 41,910 years ago (give or take 500 years) on the Siberian steppe... Read more Astronaut newts that self-harm02/06/14
On board the Russian satellite Bion No.7 were ten rats, two rhesus macaques, over a thousand fruit flies, and ten newts. Humans weren’t allowed on this biomedical space mission; they were waiting for the return of their experimental organisms hoping to gain insights into the effects of a weeklong sojourn orbiting the Earth.
Each animal had a specific purpose on this spaceflight of 1985. The two macaques, called Gordy and Verny, for the effects of microgravity on balance and blood flow, as well as any side effects of solar radiation. The fruit flies for their energy consumption while transforming into their adult stages. And the Iberian ribbed newts were on board to understand the effects of spaceflight on wound healing. The latter seems to be enhanced both during and following their travels, but the handful of studies undertaken during the 1980s and 90s are still largely ambiguous. Inhabiting ponds, cisterns, and other aquatic habitats of Spain, Portugal, and Morocco, Iberian ribbed newts (Pleurodeles waltl) – like the laboratory amphibian Ambystoma mexicanum or axolotl – are able to re-grow lost limbs and their tail as if they are exempt from the worries of serious injury. On terra firma, this capability has fascinated scientists since Italian biologist Lazarro Spallanzani first chopped the limbs off salamanders in the 1760s and judiciously recorded what happened next. Today, this is still the basic premise of regenerative biology; chop off a limb, a tail, or excise the lens or retina and see what happens. But only recently, with advances in molecular biology, have scientists begun to tease apart the details of their regenerative prowess... Read more. Misshapen and Battered Stems of Great Beauty22/05/14
To understand ageing some scientists frequently stitch two mice together. Right flank to left flank. Old mouse to young mouse. As they recover from this unexpected pairing, their circulatory systems fuse; blood from one flows through the new vascular connections into the other, and vice versa – what’s mine is yours.
And it is this mixing that the scientists are interested in. With young blood pumping through its veins, the muscles and brain of the older mouse are rejuvenated, according to two studies published earlier this month. Interestingly, the same result was found when the young blood’s plasma was isolated and injected into older, non-conjoined mice. Red blood cells, white blood cells, and platelets aren’t required it seems. The reason that mice, humans, and most other organisms age is largely due to a substandard replacement of cells. Stem cells generate these replacements, but become less adept at doing so over time – as our cells get tired so do we. But since the aforementioned blood transfusions can revitalise this process, it seems that signals from the blood are the prime cause of the faltering of stem cells. Consequently, researchers are investigating a few candidate proteins contained within plasma that may be involved in this anti-ageing process. For us warm-blooded mammals this is an inescapable facet of life – we all senesce. But for a few organisms found on Earth this is of little concern. Read more... The Mammal With a Ghillie Suit14/05/14
There is more to sloths than videos of them crawling across verdant lawns or being held in buckets. They have a particularly peculiar evolutionary history, and we are only beginning to unveil their secrets.
Up until 10,000 years ago, giant ground sloths reached heights of over four metres (in the case of Megatherium), stood on their hind legs to reach tasty leaves above, used their powerful forearms to dig equally giant holes in the ground, and enjoyed a troglodytic existence from time to time. Even earlier still, members of the Thalassocnus group started to part from their terrestrial lifestyles. Off the coast of Peru, the leg bones of one group of sloths became more and more compact over time, strongly indicating that they enjoyed a semi-aquatic lifestyle. But these oddities are long gone. Today, relatives of these creatures can be separated into two groups: the two-toed and three-toed sloths. The latter of which have continued the groups’ penchant for the peculiar to the greatest extent. Read more... Ancient Shark Fossil Reverses Long-Held Views
22/04/14
The term “living fossil” is commonly used, oxymoronic, and misleading.
The two words were first united by Charles Darwin near the beginning of On the Origin of Species, “These anomalous forms may almost be called living fossils; they have endured to the present day, from having inhabited a confined area, and from having thus been exposed to less severe competition.” The iconoclastic naturalist was referring to the duck-billed platypus and South American lungfish, and chose his words carefully (italics added)... Piranhas are Masters of Gurning, Biting, and Tooth Loss16/04/14
Piranhas make it very hard for people trying to find out more about their lives. They live in some of the most impenetrable areas of South America, have scissor-like jaws, and, when stressed during the dry spells, have an aggressive nature to match. Even when they are dead and stored in museums collections they aren’t willing to give up their secrets...
The Fish That Didn't Need Their Eyes, Colour, or Wariness
11/04/14
If you drop a small pebble into a stream any fish nearby will usually flee as if the watery gates of hell have been opened. Do the same in an underground stream in Mexico, however, and the fish will come for a closer inspection. With no predators and ephemeral food supplies, it pays to be inquisitive in caves...
The Shrimp That Grow Light Sensitive Wings to Avoid Getting Into Hot Water
04/04/14
If you shine a torch across the African savanna you are likely to see pairs of lights shining back at you. Lions, hyenas, a serval, or thousands of wildebeest all have a reflective layer at the back of their eyes – the tapetum lucidum – that bounces photons back across their retinas, increasing their chances of detection. This biological mirror makes their eyes shine. The same is true 3600 metres down in the Atlantic and Indian Oceans where hydrothermal vents, known as black smokers, churn out the intense heat of the Earth’s molten core. Thousands of pairs of eyes shine back at you...
Not Seeing the Forest for the Tree (of Life)
29/03/14
We humans have a natural tendency to categorise things: books in a library, food in a supermarket, elements in a periodic table, and the cornucopia of organisms that we share this planet with. However, mainly due to lack of understanding, the latter have been ordered incorrectly time and time again. We also have an ongoing tendency to be wrong...
Breaking the Seven-Minute Record20/03/14
On January 6th, 2000, a tree in the Spanish Pyrenees fell on an elderly mountain goat called Celia. Such a chance event would usually go without notice, except from scavengers and decomposers that would begin to consume the carcass. But her death triggered an alarm call...
A 30,000-Year-Old Virus From Siberia20/03/14
The permafrost that lies underneath the Artic tundra has become a hot topic of late. Its melting as a result of global warming – of which is most pronounced in the polar regions – is releasing huge amounts of greenhouse gases, that in turn are further contributing to climate change. Exceptionally preserved mammoths have also been found frozen in time, raising the hopes of some scientists to one day resurrect these iconic megafaunal fuzz balls...
Comic Book Creatures13/03/14
The abilities of superheroes and super villains aren’t restricted to the pages of fantasy; animals have been using similar strategies for survival and communication for millions of years.
ILLUSTRATIONS by KETKI MUDHOLKAR
Five Animals That Smell Oddly Familiar19/01/14
Although they are communicating their willingness to mate or defend a territory, sometimes an animal's smell can remind us of something very familiar. Cinema treats and illegal drugs included...
A White Tiger From Rewa15/01/14
On May 27th, 1951, a male tiger cub with white fur was captured in a jungle near Rewa, central India. His mother and three nine-month old siblings were shot because of their normal colouration.
Following his capture by Mathand Singh, the Maharaja of Rewa at the time, this rare cat was transported to a deserted palace, caged, named Mohan, and eventually coupled with an orange female... Go Home PR team, You're Drunk13/12/13
As you scour through the Internet today, you may come across such hyperbolic headlines as “The genetic code has a double meaning” or “Scientists discover double meaning in genetic code”. They convey a certain importance hitherto unknown. Unfortunately not...
How Horseshoe Crabs Ensure Your Health12/12/13
When I was one year old I had an injection against measles, mumps, and rubella, as did 90% of the baby population. Following this “short sharp scratch”, intravenous therapies are a common occurrence in our lives. They provide protection against the most recent influenza scare and make a gap yah travelling possible. In any case, you have horseshoe crabs to thank for your life...
Why The Selfish Gene Can Live07/12/13
Since its inception in 1976, The Selfish Gene has generated a lot of ambivalence and general brouhaha. Even its author, Richard Dawkins, has stated that the use of “selfish” may have been a mistake as its meaning is easily misconstrued. The term “selfish” was chosen – among other altruistic reasons – because evolution should be viewed at the level of the gene. It is genes that selfishly compete for survival. Consequently, if he could time travel back to the time of “Wordsworth’s blissful dawn”, he may have named the book “The Immortal Gene” since it is genes that are forever passed on (if successful). Hosts die, but the gene prevails...
Looking Into the Past Using Displaced Eyes26/11/13
A major division in the animal kingdom is founded on when the anus or mouth emerges during early development. If you’re anus develops first then you’re a “deuterostome”; looking at you starfish, sea cucumbers, and those of us blessed with a backbone. Conversely, in worms, insects, and most of the other wriggly or slimy invertebrates on Earth, a mouth develops first. These are the “protostomes”. Despite this fundamental discrepancy in evolutionary history, a study in the 1990s traversed this anus/mouth barrier and introduced DNA of a mouse into the leg of a fly...
Why Are Komodo Dragons So Big?24/11/13
They’re venomous and have relatively good oral hygiene for predatory animals–contrary to previous beliefs. But why are Komodo dragons so big compared to other lizards found around the world? It seems almost a truism: the largest lizards on Earth are big so that they can victimise large prey. But there is more to this story than meets the eyes of today...
One Sense Evolved From Another in Ancient Fishes14/11/13
Imagine being able to notice those around you not only by sound or sight, but by the electrical signals they emit as their muscles contract. It would certainly make any effort in a game of hide-and-seek futile. But this ability is found among a few fortunate members of the animal kingdom. Platypuses, dolphins, salamanders, and bees can detect slight changes in electric fields to perceive the world around them, whether it is to detect hidden prey or evaluate how often a flower has been visited by other pollinators (yes, bees in this case).
Yet, these particular ‘sixth senses’ arose independently – and long after – those of the most ancient fish groups.... Page 2 |
AboutFrom our most distant relatives to our close primate cousins, these are my elaborations on the natural world
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