Ponder Degrees Of Acuity


New research by Eleanor Caves at Duke University suggests most species view the world in less detail than us Comparison of visual acuity in 600 species of animals, birds, fish and insects conclude humans see fine detail elusive to most species. Based on spacing and density of light sensing structure in eye anatomy, the study measured acuity in terms of cycles per degree, translation – how many pairs of black and white parallel lines a species can discern within one degree of the field of vision before they turn into a smear of gray.

Average human eyes resolve 60 black/white cycles per degree of acuity. Anyone with less than 10 cycles per degree of acuity is legally blind. Most insects can’t see more than one degree of acuity. Fish and birds hover around half the visual acuity of humans. (One exception birds of prey – Australian web tailed eagles boast 140 cycles per degree )) Cats and dogs perceive 7 times less visual detail, slightly more than goldfish, significantly more than rodents.

Evolutionary perfection compensates lack of visual acuity with species specific tweaks of survival fancy. Sight as we know it is not the measure of life on Earth.

 

Image result for kitchen as seen by different animals

https://www.smithsonianmag.com/smart-news/humans-see-world-100-times-more-detail-mice-fruit-flies-180969240/

 

The image on the left shows the wings of a map butterfly as they might look to a jay looking for a snack, and on the right, to another member of its kind, such as a rival or potential mate. Image courtesy of Eleanor Caves

The image on the left shows the wings of a map butterfly as they might look to a jay looking for a snack, and on the right, to another member of its kind, such as a rival or potential mate. Image courtesy of Eleanor Caves

Image result for eleanor caves acuity

A spider web as seen in bird vision (left), and fly vision (right). The zigzags on the spider’s web send a secret message to birds that their insect prey can’t see, even from less than a foot away. Image via Eleanor Caves.

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Death Of Our Oldest Spider, Zombie Caterpillars And Masquerading Ant Butt Beetles


Fellow Worpresser Peter ( https://ppazucha.wordpress.com/ ) sent word of a tragic arachnid death. The world’s oldest spider, a female Australian trapdoor spider known only as Number 16 was found dead in her burrow at age 43. Number 16 didn’t succumb to old age, her death is credited to a parasitic wasp attack. Wasps enter burrows laying eggs in or on the spider. When eggs hatch, larvae eat the spider from outside in or inside out. Number 16 was identified in 1973 by Barbara York Main, the University of Western Australia arachnologist known as “the spider lady”, part of Main’s trapdoor spider population study in the central wheat-belt of Western Australia. Before Number 16, a 28-year-old captive Mexican tarantula held the title of oldest known spider. Curse you parasitic wasp, RIP Number 16.

Image result for number 16 dies burrow

Image result for number 16 dies burrow

http://www.cbc.ca/radio/asithappens/as-it-happens-monday-edition-1.4641540/the-world-s-oldest-spider-was-killed-by-a-parasitic-wasp-1.4641544

It’s impossible to Google death of world’s oldest spider without stumbling upon a plethora of insect peculiarities.

Chris Miller, project manager of the Wildlife Trust for Lancashire, Manchester and North Merseyside, England discovered a lethal virus that turns caterpillars into zombies. Baculovirus affects how caterpillars’ brains react to sunlight and forces them to make a death march towards treetops in the middle of the day. Zombie caterpillars march to the treetops and die. Their bodies liquefy, the virus bursts out of their corpses and drips onto victims below.

What remains of an oak eggar moth caterpillar after it climbed to the top of a tree and liquefied. (Chris Miller)

http://www.cbc.ca/radio/asithappens/as-it-happens-wednesday-edition-1.4232025/a-virus-in-england-is-turning-caterpillars-into-exploding-zombies-1.4232030

Hats off to Nymphister Kronaueri, a new species of beetle identified by Christoph Von Beeren, an ecologist at Germany’s Technische Universitaet Darmstadt while studying army ants with his colleague Daniel Kronauer in the Costa Rica rainforest, spring 2014. Camped in the jungle, watching army ants by lamplight, they noticed ants with double butts. Closer inspection revealed another example of specialized adaptation in the natural world. Evolutionary whimsy decreed army ants wouldn’t notice a stowaway beetle masquerading as an ant ass. Army ants are apex predators, voracious marauders stinging, dismembering and devouring unfortunate spiders, birds, snakes and small animals along the way. Over 300 insect species shadow ant armies feeding on scraps. Science doesn’t know why, but for what must be a very good reason nature insists a piggy-backing ant butt beetle gets first crack at the buffet.

From above, it’s hard to tell this army ant has a beetle attached to its rear. (M. Maruyama)

http://www.cbc.ca/radio/asithappens/as-it-happens-wednesday-edition-1.3984065/is-it-a-butt-or-a-bug-newly-discovered-beetle-masquerades-as-ant-s-backside-1.3984071

 

Pondering Honey Fungus


What is the largest organism on Earth? Simple enough question, take a shot at the answer – giant sequoia, blue whale – not even close. Ponder a 5.5 kilometer across honey fungus in Oregon, our largest terrestrial organism.

Image via Factorialist.

https://www.theatlantic.com/science/archive/2017/10/humongous-fungus-genome/544265/

Fungus inhabit the kingdom of Fungi. Neither plant or animal, science suspects member species of the fungal realm number in millions. Of 120,000 identified species –  300 are detrimental to humans, 8,000 attack plants, many more target animals. Before dismissing fungus as mushroom soup or nasty toenails, ponder a parasitic community boasting the largest organism on Earth.

Science defines individual life forms as organisms comprised of genetically identical cells, able to communicate and share a common purpose. Weighing an estimated 600 tons, Oregon’s behemoth Honey Fungus passes the single organism test with flying colours. Don’t go looking for a giant mushroom, most of this fungal monstrosity lurks below ground. A parasitic giant, entwined underground in colonized tendrils intent on dissolving roots of conifer forests above.

http://factorialist.com/fungus-tree-eating-machine/

http://earthsky.org/earth/largest-land-organism-honey-fungus

Fungi don’t photosynthesize, sustenance comes from absorbing nutrients dissolved by secretion of digestive enzymes. Science can’t say if it took two or eight thousand years for the world’s largest organism to occupy 2,384 acres, roughly the area of 1,665 football fields. It can say the largest individual organism on Earth is a fungal parasite named Honey. A mysterious, organic matter dissolving monster capable of sucking life from all it touches. Fungi freak me out.

Asperitas


For the first time in over 50 years, skies are officially cloudier. This year maestros of meteorologic whimsy, conduits of foreboding trepidation and petticoats of nature’s fancy were asked to make room for Asperitas at the head table. Gavin Pretor-Pinney, founder of the Cloud Appreciation Society inducted Asperitas into the International Cloud Atlas hall of fame. A monumental achievement in science clouded by genre, subsection, supplementary features and special circumstance.

https://cloudatlas.wmo.int/clouds-supplementary-features-asperitas.html

Gavin Pretor-Pinney defined Asperitas as –

… localized waves in the cloud base, either smooth or dappled with smaller features, sometimes descending into sharp points, as if viewing a roughened sea surface from below. Varying levels of illumination and thickness of cloud can lead to dramatic visual effects.

An asperitas formation over Ballstad, Vestvagoy, Lofoten islands, north of Norway.

If by chance you happen upon undulating clouds that resemble rough seas if viewed from below – shout a hearty welcome to Asperitas, the first cloud formation recognized in half a century.

What Have I Done


Chances of finding someone who shares relaxed indifference toward a Black Widow spider living 18 months in their basement window are slim to none. Likewise genuine remorse for basement widow’s unceremonious death, or wobbly knee outrage over vacuum hose eradication wielded by a concerned family member. I sulked for weeks, outraged by audacity of family capable of decisive spider intervention while I was away.

“I liked that spider, it wasn’t bothering you!” met “Are you nuts? Have you seen what a Black Widow bite can do?”. Yes I replied, but you don’t understand, this spider liked the basement window. Knowing they acted reasonably didn’t ease the loss of basement widow.

I haven’t told them basement widow’s polite demeanor might have been a peculiar anomaly. Nor have I divulged “what have I done” alarm over recent Black Widow sightings. Widows I might add, who by all appearances lack the courtesy of basement widow. Three Black Widow encounters in the past two days, all eluding attempts to catch and release, not one downstairs where they belong. Oh my, what have I done.

These widows are feisty, smaller and alarmingly craftier than the soothing persona of basement widow. One in windowsill cactus above my kitchen sink, another attempting to claim the bathroom window, a third exuding what you gonna do about it confidence between folds of the spare bedroom curtain. What have I done? Three allowed themselves to be seen, how many lurk unseen.

RIP House Widow


On a trip to the laundry room several years ago I discovered a black widow spider. As the only family member licensed to dispatch spiders, her demise was automatic and swift. My husband protected us from snakes, spiders were my responsibility. A practical, unspoken arrangement acted upon without hesitation, quelling arachnid hysteria never bothered me. If a snake ever hissed in the house my husband would do the same. I forgave the one and only house snake in our 35 years, the garter snake he and the kids brought home in a bucket, the one they named Mrs. Slithers when she gave birth to 11 babies the following day, but that’s another story.

Soon after finding laundry room widow, many more disturbed domestic harmony. Upstairs, downstairs, bathroom, kitchen, bedrooms – black widows were becoming a problem. Some had to be executed, but only as a last resort when catch and release failed. Along the way a peculiar affinity developed for well mannered widows. Rogue spiders couldn’t be allowed to roam at will, homesteaders were another matter.

For a while “No, of course I don’t want a black widow bite”, “Yes, I’ll do something about basement widow” sandbagged rising dismay. Relax! Spiders are my job, the situation is under control!

My son broke the news. “You were sleeping…” “We saw an egg sack…” “Sprayed it with Raid…” “Got the vacuum out…” I heard myself say, you killed my spider? Then wished I could take it back because it sounded so crazy. “We can get you a pet spider” he offered with genuine sympathy. “It’s ok, I don’t want a pet spider” was spoken, “I liked that spider” wasn’t.

I couldn’t explain without sounding unbalanced, wouldn’t expect them to understand mild obsession with observing the same spider for almost 2 years. Their spiders are my snakes, I get it. RIP basement widow.

 

Basement Widow Update


Basement widow hasn’t crossed my mind in a while. Paid a visit after work tonight, snapping a hasty cell phone image of her impressive domain.

Research indicates female black widows have a life span of up to three years. My spider is entering her second basement summer. Rest easy, I’ll update her status every few months.