Horseshoe Crabs

 

HorseshoeCrab1opt

HorseshoeCrab2opt

Everyone knows horsehoe crabs are a evolutionary throwback to prehistoric times.  What many don’t realize, however, is the value these creatures hold for the modern scientific and medical industry.

In 1956, scientist Frederick Bang published a paper describing the fascinating capability of the crabs blue-colored blood to detect foreign pathogens and form a gelatinous substance to surround (but not kill) the invading microorganisms.  The crab blood can sense even the tiniest concentration of pathogen – one part per trillion – and will form the gel clots right away.  The pathogen can then be isolated inside the gel by scientists and identified.

This is what makes it so valuable to the biomedical and pharmaceutical industries.  The modern test for contamination using horseshoe crab blood is called LAL (for Limulus amebocyte lysate), and is actually required by the FDA on all new drugs and surgically implanted devices and prostheses.

At several large ‘blood farms’ on the east coast of the United States, adult horseshoe crabs are collected from their coastal habitat and bled.  After a percentage of their blood has been collected, they are nursed back to health and released into the wild again.  The process is similar to a human donating blood, except it occurs in a tightly controlled sanitary environment, and is obviously not voluntary.

These photos, taken at the Mount Desert Oceanarium in Bar Harbor show the interpretive guide explaining to visitors how horsehoe crabs digestive and reproductive systems work.

Centruroides Scorpion with closeups of pectine organ and face

scorpion1opt

Scorpion-Pectine-Organ1opt

scorpion2opt

Most scorpions don’t need to use their stingers for killing prey.  If the menu consists of another insect, scorpions are normally quick enough to snatch  and dismember it with their pincers, dissolve the body parts with enzymes from their mouth, then ingest what remains.

Depending on the species, a scorpion can have from 2-12 eyes, though in spite of this, their vision is subpar compared to other insects.  Scorpions rely on abdominal sensory organs called pectines to sense fine chemical details in their environment.  Pectines have the appearance of small legs with feathery appendages, and transmit chemosensory and mechanosensory information to the scorpion’s brain.

In North America scorpions are more widespread than most people realize.  They are typically nocturnal hunters, though in hotter climates they will move around at any hour to seek out cooler resting quarters.  In the Southwest, scorpions are common household pests, posing a threat to curious children, pets, and anyone unlucky enough to step on or near one.  With the exception of the Arizona Bark Scorpion however, the venom from most species is not any more harmful than a wasp or hornet sting.  Interestingly, the source of home invasions by scorpions is often tree branches that overhang a house’s roof.  Scorpions climb the trees, loose their grip or are blown off, and fall down to the roof.  Once on the hot roof surface, they quickly scoot into attics through eaves and vents in search of cooler surroundings.

Sharp Shinned Hawk – Medford, MA

SharpShinnedHawk1

This large juvenile ‘Sharpie’ is dining on a mockingbird in suburban Boston.  Easily confused with juvenile Cooper’s Hawks, young Sharp Shinned Hawks tend to be slightly smaller and have less feather coverage on their legs.  Their breasts are streaked with brown spots and lines, unlike the Coopers mostly white lower breast area.

Both species feed exclusively on other birds, ambushing them in the air or at bird feeders.  Sharpies will usually take their dinner up to a branch to pluck and eat it, except in winter when they don’t seem to mind enjoying their meal on the ground.

This bird was a remarkably efficient eater.  When he flew away, all that remained of the prey were a beak and gizzard.

Reef Life – Culebra, PR

Reef-Fish-build2opt

Reef-Fish-Build1opt

The quantity and diversity of marine life on the reefs of Culebra and Vieques is mindblowing.  Both islands are still low-key and affordable for visitors from the United States, and there is no charge for beach access or even parking.  Once underwater, the array of tropical species is immediately apparent, even in the first five inches of depth.  For that reason, it’s important to begin floating right away instead of stomping out to waist level and destroying the delicate life underfoot.

Each time I return, I look forward to the exhilaration of finding a sea turtle, eagle ray, spiny lobster, or other large, elderly creature. My favorite underwater moments however, are being surrounded by the hundreds of familiar – yet peculiar – fish, all going about their lives just inches away from me.  It’s like meeting up with your old friends at summer camp every year.

Large, flamboyant Queen and Stoplight Parrot fish (second column, middle photos) are everywhere, scraping bites of algae off the rocks with their large front teeth.  More secretive is the Four Spotted Trunkfish (bottom right), almost two feet long, hiding quietly under a coral overhang.  Filefish (first column, third photo) come in several varieties here; this is the White Spotted one.  All are woefully ugly, with faces that appear to be drawn by a toddler.  They drift slowly near the reef bottom in search of tasty algae and coral snacks.

Ebony Jewelwing

What makes Ebony Jewelwings special is their ghostlike manner of fluttering through the air.  When you first see them in the woods, usually near a creekbed, it’s not immediately clear that they are damselflies; with their gently flamboyant wing movements, Jewelwings appear more like butterflies.   Though not captured well in this photo, the body length of these beautiful odonatas is a deep metallic blue or green.

Lake Erie

lake-erie1opt

Carpet Beetle Larvae

carpetbeetlelarvaeComp1opt

It’s so unfair that a creature this small can inflict such pain and misery.  Carpet beetles are tiny, nondescript bugs that live in most homes and eat all types of organic matter. Some of their favorite things to snack on are the small amounts of skin that we shed every day.

The problem with carpet beetles is their larvae.  The fine bristles covering the larvae produce itchy and painful swelling where they come in contact with human skin.  Many people afflicted by these tiny demons initially think they have encountered bedbugs.  The allergic reaction to carpet beetle larvae however is more painful and less itchy than bedbugs.

The toothbrush is shown to give perspective on how tiny these creatures are.  Their painful ‘bites’ last for several days to two weeks, often causing referred pain in nearby lymph nodes.  The best way to avoid carpet beetles is to clean and vacuum your house fastidiously.

 

Follow

Get every new post delivered to your Inbox.