Biology

In fossilized fish eye, rods and cones preserved for 300 million years

Scientists have discovered a fossilized fish so well preserved that the rods and cones in its 300-million-year-old eyeballs are still visible under a scanning electron microscope.

It is the first time that fossilized photoreceptors from a vertebrate eye have ever been found, according to a paper published Tuesday in Nature Communications. The researchers say the discovery also suggests that fish have been seeing the world in color for at least 300 million years.

Continue Reading.

4

ALL THE PLASTIC IN THE OCEAN MEASURED IN WHALES

After spending six years sampling the seas, scientists can say that there are AT LEAST of 5.25 trillion pieces of plastic floating on out there. That adds up to about 269,000 TONS of the stuff. Most of that comes from discarded fishing gear — nets and other large debris — but a not-insignificant chunk comes from less auspicious sources, including microbeads in cosmetic products.

This was actually less plastic than the researchers expected to find at the surface. They suspect the missing plastic is likely being eaten by organisms, or otherwise mulched by the gyres, and sinking deeper into the oceans. (That probably isn’t a good thing, since microplastics may introduce unknown pollutants into the ecosystems we rely on for food.)

But it’s still a LOT! If you can’t wrap your head around just how much plastic that really is, CityLab helpfully drew a comparison to this non-plastic thing you might find in the ocean: An adult blue whale who weighs between 100 and 150 tons. Which means THIS is how many whales’ worth of plastic are floating around out there. That’s 2,150 whales.

4

Jackson´s chameleon (Trioceros jacksonii)

Jackson’s chameleon is an African chameleon belonging to the chameleon family. There are three subspecies. Jackson’s chameleons are native to the humid, cooler regions of Kenya and Tanzania, East Africa, and found in great numbers at altitudes over 3,000 m. Most chameleons are oviparous, but Jackson’s chameleon gives birth to live offspring. 8 to 30 live young are born after a five- to six-month gestation.They are sometimes called three-horned chameleons because males possess three brown horns. Jackson’s chameleons live primarily on a diet of small insects. They are less territorial than most species of chameleons.

photo credits: wiki, Benjamint444, Linda Davison, golizards

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more…..
PAIRS at the SHEET

(click images for IDs in captions)

I use a 125W Mercury Vapour lamp for attracting night-flying insects. I used to set this up on my apartment rooftop or balcony with a white sheet and the surrounding tiled or painted walls as a base. I found this fairly limiting due to often small numbers of attendees and usually the same species. So now I have invested in a gasoline generator and take my gear into the bush strapped to the back of my trusty electric bike.



The upside of this is an endless variety of species of all sizes, not only moths but from across the arthropod range; the downside is being totally overwhelmed by the sheer volume of insect life to the point where getting settled on the sheet is difficult due to a constant barrage of disturbances, disrupted fields of view for a clean photograph, and predation (an army of predatory wasps and mantids require employing your peripheral vision to be aware of your prize model potentially becoming dinner). Of course, other subjects might alight near the sheet on the ground or surrounding vegetation and they can be photographed there.

(NB. I use the light only for photographing night-flying insects. I do not trap or collect specimens.)

The hard decision is usually deciding when to pack up and go home, just in case that “amazing one” arrives…..

by Sinobug (itchydogimages) on Flickr.
Pu’er, Yunnan, China

You can see all of my images captured at the night light in my Flickr album, Night Light.
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Tall, Dark and Handsome: The Southern Cassowary

As tall as a human with striking black plumage and a vivid blue and red neck, the southern cassowary (Casuarius casuarius) is Australia’s heaviest flightless bird. It’s one of three species of cassowaries in the world, and is part of an ancient group of flightless birds including the emu, the ostrich, and the kiwi.

The southern cassowary is found throughout Western and Southern New Guinea, as well as the tropical rainforests, swamps and mangrove forests of North-Eastern Australia. They’re instrumental in maintaining the diversity of their rainforest homes, because they’re frugivores—fruit eaters—and they act like natural gardeners, consuming seeds and then re-distributing them over a widespread area through their dung.

image

In Australia there are only three distinct populations, totalling around 2200 individuals, so they’re listed as endangered. Since European settlement, the cassowary’s habitat has been reduced to around 20-25% of its original size, and other big threats include being struck by vehicles, dog attacks, interactions with humans, and disease.

Cassowaries mate throughout winter and spring (June to October), with females mating with more than one male and producing several nests of large, olive-green eggs. The males are responsible for incubating the eggs and raising the chicks until they’re about 9 months old, when he chases them off to survive on their own.

image

Atop their head, cassowaries have a sort of helmet: a hard brown “casque” that’s spongy on the inside. Its purpose isn’t fully known, but researchers think it could be used to display dominance and age, to help with hearing—as cassowaries make low, vibrating sounds—or to act as a shock-absorber as it races through thick rainforest and scrub.

According to the Guinness World Records book, the cassowary is the most dangerous bird in the world. At up to 2 metres tall and 75 kg in weight, cassowaries can reach speeds of 40 kilometres per house with their strong, muscled legs. On each of their six toes, they have dangerously sharp claws that reach up to 12 centimetres long. When threatened, the cassowary will kick out, and uses the claws to rip at and fight with other birds. Attacks on humans are rare, and there’s only one known instance where  a person was killed. In 1926, a group of boys were hunting a cassowary near Mossman, North Queensland, when the cassowary turned and chased them. One fell over and was killed when the cassowary’s claw slashed the jugular vein on the boy’s neck. Pretty clear message there: don’t hunt them, don’t get hurt.

Want to help this threatened species? Check out Cassowary Recovery Team or donate to Cassowary Conservation.

(Image Credit: Wikimedia Commons)

Ants show left bias when exploring new spaces

University of Bristol

PhD student Edmund Hunt and colleagues studied how Temnothorax albipennis ants explore nest cavities and negotiate through branching mazes. They found that ants were significantly more likely to turn left than right when exploring new nests. Such left bias was also present when the ants were put in branching mazes, though this bias was initially obscured by wall-following behaviour.

So why do the majority of rock ants turn left when entering unknown spaces?

Edmund Hunt said: “The ants may be using their left eye to detect predators and their right to navigate. Also, their world is maze-like and consistently turning one way is a very good strategy to search and exit mazes.

"Furthermore, as their nest-mates are left-leaning too, there should also be safety in numbers. Consistent turning may also help the ants to monitor nest mates during house hunting. So perhaps leaning left is more shrewd than sinister."

Paper:  ‘Ants show a leftward turning bias when exploring unknown nest sites’ by Hunt ER, O’Shea-Wheller T, Albery GF, Bridger TH, Gumn M, Franks NR. in Biology Letters

Caption: In a study published in Biology Letters, researchers from the University of Bristol, UK found that rock ants instinctively go left when entering unknown spaces. Credit: Edmund Hunt, University of Bristol, UK

Image: Tatiana Makotra/Shutterstock.com

This is how blue eyes get their colour

Blue eyes don’t get their colour from pigment - it’s actually way more fascinating than that.

FIONA MACDONALD   20 DEC 2014

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Your eyes aren’t blue (or green) because they contain pigmented cells. As Paul Van Slembrouck writes for Medium, their colour is actually structural, and it involves some pretty interesting physics.

As he explains, the coloured part of your eye is called the iris, and it’s made up of two layers - the epithelium at the back and the stroma at the front.

The epithelium is only two cells thick and contains black-brown pigments - the dark specks that some people have in their eye is, in fact, the epithelium peaking through.

The stroma, in contrast, is made up of colourless collagen fibres. Sometimes the stroma contains a dark pigment called melanin, and sometimes it contains excess collagen deposits. And, fascinatingly, it’s these two factors that control your eye colour.

Brown eyes, for example, contain a high concentration of melanin in their stroma, which absorbs most of the light entering the eye regardless of collagen deposits, giving them their dark colour.

Green eyes don’t have much melanin in them, but they also have no collagen deposits. This means that while some of the light entering them is absorbed by the pigment, the particles in the stroma also scatter light as a result of something called the Tyndall effect, which creates a blue hue (it’s similar to Rayleigh scattering which makes the sky look blue). Combined with the brown melanin, this results in the eyes appearing green.

Blue eyes are potentially the most fascinating, as their colour is entirely structural. People with blue eyes have a completely colourless stroma with no pigment at all, and it also contains no excess collagen deposits. This means that all the light that enters it is scattered back into the atmosphere and as a result of the Tyndall effect, creates a blue hue. 

Interestingly, this means that blue eyes don’t actually have a set colour - it all depends on the amount of light available when you look at them.

Structural colouration also gives colour to butterflies, beef and berries, as Van Slembrouck points out.

It’s pretty mind-blowing stuff. Van Slembrouck writes for Medium:

“Imagine that you could shrink yourself to a microscopic size and then climb through the mesh of fibres in the stroma. That’s where structural colouration is coming from…

… and in the mesh are also strands of smooth muscle tissue that contract to dilate (expand) the pupil, pulling the inner edge of the iris toward the outer edge. When this happens, the stroma fibres slacken and may become wiggly as tension is released. This makes me wonder, does that slightly alter the colour of your eye as well?”

Check out Van Slembrouck’s great story to find out how hazel and grey eyes get their colour, and also to check out his beautiful diagrams that explain structural colouring.

Source: Medium

How do plate tectonics play a role in this lion’s diet?

By definition, soil must be capable of supporting life, and so soil is the foundation of how the food chain operates on land. The food chain describes the movement of energy and nutrients through the biosphere from plants to herbivores and carnivores. Over the long term, plate tectonic processes play an important role in this movement because tectonic processes introduce inorganic chemicals to Earth’s surface. (via Physical Geology Today – The Food Chain)

Albertosaurus sarcophagus

image

Source: http://fc05.deviantart.net/fs71/i/2012/103/d/f/alberta__s_feathered_tyrant_by_dinohunter000-d4w0syb.jpg

Name: Albertosaurus sarcophagus

Name Meaning: Flesh-eating Alberta Lizard 

First Described: 1905

Described By: Osborn

ClassificationDinosauria, Saurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Tyrannosauroidea, Tyrannosauridae, Albertosaurinae

Albertosaurus is a relatively famous tyrannosaur, having been depicted in many works of media and being presented often as the smaller cousin of the much more famous Tyrannosaurus. However, this guy was a really neat dinosaur in its own right, and one of my favorites. It is known from a wide variety of fossil specimens, including a bone bed with twenty-two individuals in the same location, and in general it is found in Alberta, Canada, what a huge surprise. It was a large carnivore, up to 10 meters long, and up to 4 meters high. It lived in the Campanian age of the Late Cretaceous, from 71 to 68 million years ago, and should not have crossed paths with Tyrannosaurus. Like Tyrannosaurus, it was a massive bipedal predator, with small arms, and a deep skull, designed to have a huge bite force to better hold struggling prey. It had short bony crests above the eyes that may have been used for display and courtship.  

image

Source: http://stygimolochspinifer.deviantart.com/art/Albertosaurus-in-the-Snow-352103085

The dry island bonebed featured a huge group of these dinosaurs, with large numbers of bones and many individuals of various ages, including a two year old and a very old, very large individual. This has allowed for a good growth record of the animal to be placed together, with the youngest individual being about 2 meters in length, indicating an S shaped growth curve, with the most rapid growth occurring in a four year period from 12 years old to 16 years old, strangely similar to the human growth curve. Most Albertosaurus that have been found died in adolescence, around 14 years old, with juvenile specimens rarely found, potentially due to small size and fragile bones. There were probably higher infant mortality rates, which has just not been observed due to fossilization bias. Furthermore, the bonebed indicates that these animals may have hunted in packs, given the absence of prey organisms in the bonebed indicating that this site was not a predator trap. They lived in family groups with adults, sub-adults, and juveniles, hunting together and working together to do so - smaller individuals doing more running, larger individuals using more force on prey, filling different niches but working together to hunt.

image

Source: http://pheaston.deviantart.com/art/Albertosaurus-326541177

Albertosaurus lived amongst peat swamps, lagoons, estuaries and tidal flats, as well as deltas and floodplains; a very wet world. It lived alongside many species of fish, mammals, and the plesiosaur Leurospondylus, as well as turtles and crocodilians. It lived alongside many species of dinosaur, especially hadrosaurs such as Edmontosaurus, Saurolophus, and Hypacrosaurus, ceratopsians, ornithomimids, ankylosaurus, pachycephalosaurus, and many other theropods such as troodontids, dromaeosaurids, caenagnathids, and Albertosaurus was decidedly the apex predator of the region. 

 Sources: 

http://en.wikipedia.org/wiki/Albertosaurus

http://www.prehistoric-wildlife.com/species/a/albertosaurus.html

Shout out goes to my friend crazedcrocgirl!

SOURCE

Chilong Titanus (Titan Demon Dragon), at first glance from Intel holograms, appear as rather placid and ungainly looking beasts but when encountered in person they are an intimidating force. They are the largest predator on Yesei and the most bizarre due to the fact that they are the only liquivores on the planet and they go through metamorphosis. As young, they are puny and quick, equipped with massive jaws that will lash out at anything that moves. But gradually towards their 2nd year of life the younglings will leave the comfort of their mother looking for a safe place to undergo metamorphosis. For 16 months they spend in a cocoon like shell made of their exoskeletal plates and secretions. Most will be snuffed out by opportunistic predators including other Chilong but those who survive this point of life will emerge as small yet fully developed adults. Despite their heavy build Chilong are capable of rapid bursts of speed, this becomes especially lethal as they will camouflage with the volcanic rocks and ambush any unfortunate animal that wanders by. 

Chilong are very feared among coalition soldiers stationed in Yesei’s badlands. Their thick skin can withstand blows from most automatic weapons and grenade shrapnel and there have even been reports of individuals taking several .50 caliber rounds and .40 mm grenades before succumbing to blood loss but this is unconfirmed. Chilong also will eat any soldier that gets too close. Though all predatory animals on Yesei are incapable of digesting toxic human flesh, the Chilong are the only animals that can handle human flesh. Their extremely powerful digestive acids will breakdown human cells into the most basic amino acids. Being eaten by one of the beast is a gruesome sight. Their large killing claws or its teethed lateral radular tentacles will rip into a mans torso allowing for its proboscis to makes its way through and pumping the body with acids. On the outside and organ much like a starfish stomach will dissolve skin and absorb the soupy result. Young Chilong have been known to make their way into troop barracks and become a nasty threat but are frequently eliminated with ease.

аноним спросил(а):

I have noticed that many radfems latch on to Dworkin's third point, overlooking the first two. Further, they make the third point prescriptive, rather than descriptive. Dworkin obviously meant that transgenderism will “disappear” after her androgynous feminist revolution, not that we should make actual trans people disappear RIGHT NOW or that we shouldn't allow trans people to navigate patriarchy in a way that makes life more livable ie gender self determination.

Our goal is not to make trans women’s lives a living hell. Our aim actually is completely to do with gender. Gender and sex are not interchangeable. Sex is biology - males and females. Trans women are still males. Gender is oppressive - it is females should be feminine and males should be masculine. That ideology has been used to oppress women, and still continues to do so. To focus on gender in order to defend trans women is obviously misogynistic. 

Females have been socialized to become feminine. We are not naturally anything that a male can identify as - we have specific chromosomes, hormones and anatomy that can never be replicated. That is factual. When trans women assume they are women because they feel that our gender suits them (femininity: makeup, dresses, submissiveness etc) then they are implying that gender is innate with sex. 

Males are oppressors of females. White people oppress black people. Able-bodied people oppress disabled people. So why when it comes to womanhood, can our oppressors identify with us? Biology is a real thing, and it is important. I don’t care if males want to dress femininity, behave femininely, talk femininely - but it is offensive to say that it makes them women. 

Our beef is with gender. It is the way it oppresses women. Trans women subscribing to femininity and calling themselves ‘women’ is ONE PART of our argument. When you prioritize gender, you perpetuate patriarchy. Women are not their gender, and males can not biologically be female, so the only way they can ‘identify’ with womanhood is through gender.

-Ash

Are you eagerly awaiting the snowy season in order to take a peek at what critters have been scurrying through your backyard? Studying prints left by animals is an ancient activity that was first practiced by those who depended on hunting and gathering for survival.

What’s scampering through in your area?

Animals in the family Sciuridae, such as chipmunks and squirrels, have four front toes and five hind. Look for tracks that resemble a hopping movement in which the larger hind feet actually land in front of the smaller front feet.

Another hopping critter you may find belongs to the family Lepoidae or rabbits and hares.  These tracks will look similar to that of a squirrel however, the hind feet of a rabbit tend to land at an angle rather than evenly.

Squirrel track. Photo Credit: Oakley Originals/Flickr Creative Commons

Rabbit track. Photo Credit: Canopic/Flickr Creative Commons

Animals in the family Canidae, such as

foxes

,

wolves

,

coyotes

or your neighborhood dog, have four toes on both the front and hind feet. You may also notice visible claw marks. This will help distinguish members of the Canidae (dog) family from that of the Felidae (cat) family who also have four front and hind toes, but retract their claws as they walk.

Cat track. Photo Credit: Sunny Ripert/Flickr Creative Commons

Dog track. Photo Credit: Clare Snow/Flickr Creative Commons

Tracks left by the family Mustelidae (weasel, badger, mink, skunk, and

otter

) can be identified by five toes both on the front and hind foot.  Their most likely will also be visible claw marks.

Animals such as a bear, beaver or opossum will also leave a track with five toes on the front and back.  Most likely you will be able to tell the difference between a beaver and a bear as a bear print will be MUCH larger!

Weasel track. Photo Credit: Dru/ Flickr Creative Commons

Bear track. Photo Credit: Wayne/Flickr Creative Commons

Animals in the Cervidae family include deer, elk and

moose

. Their tracks can be identified by two distinct toes.

Deer track. Photo Credit: Thomas Merton/Flickr Creative Commons

The most abundant backyard animal in the family Procyonidae is the

raccoon

. Their tracks are distinguishable by hand like print with five toes on both the front and hind feet.

Raccoon track. Photo Credit: Stonebird/Flickr Creative Commons

Tracking Tips

  • Measure the length and width of several prints. On many mammals the front feet will be larger since they support more of the animals’ weight.

  • Measure the stride (length between prints) and the straddle (width between prints), this can give you an idea of how quickly the animal was moving.

  • Look for a heel, count the number of toes and look for any claw marks.

  • Follow the tracks and note any patterns. Where do they like to hang out in your backyard?

  • Do not disturb! If the tracks lead to den or resting place, respect your backyard friend and do not disturb!

Today I took an engineer friend with me to check out a private nature preserve in Hocking County. They had over 100,000 pinned insects, a large collection of marine shells, beautiful notebooks full of exquisitely preserved leaf mines, and my reason for visiting: 50 vials of millipedes.

It took me about 3 hours to sort through them, and now they have species identifications for most of their stuff. The specimens that need more attention they’ll mail to me when I’m back in Arkansas.

I think doing things like that is one of my favorite parts of being an entomologist. The two people in charge of the collection are retired from the Dayton Museum of Natural History and were super nice and really glad to see young people interested in natural history. I get to meet so many great people in the work that I do, and their generosity is always astounding.