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Topic: Stuff you wouldn't even think to look into (Read 225 times) previous topic - next topic

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Stuff you wouldn't even think to look into
https://www.theatlantic.com/science/archive/2018/05/blood-in-the-water/559229/
Quote
Horseshoe crabs are sometimes called "living fossils" because they have been around in some form for more than 450 million years. In this time, the Earth has gone through multiple major ice ages, a Great Dying, the formation and subsequent breaking up of Pangaea, and an asteroid impact that killed the dinosaurs and most of life on Earth yet again. In other words, horseshoe crabs have truly seen some shit.

Yet, I would conjecture, some of their strangest experiences must have come in just the past few decades, as one of the soft-bodied mammals that came after dinosaurs began using their hands to scoop horseshoe crabs out of the ocean en masse. Contemporary humans do not deliberately kill the horseshoe crabs--as did previous centuries of farmers catching them for fertilizer or fishermen using them as bait. Instead, they scrub the crabs clean of barnacles, fold their hinged carapaces, and stick stainless steel needles into a soft, weak spot, in order to draw blood. Horseshoe crab blood runs blue and opaque, like antifreeze mixed with milk.

And for what exactly do humans need the blood of a living fossil? A sort of witchcraft, you might say, for it literally keeps people alive. Horseshoe-crab blood is exquisitely sensitive to toxins from bacteria. It is used to test for contamination during the manufacture of anything that might go inside the human body: every shot, every IV drip, and every implanted medical device.

So reliant is the modern biomedical industry on this blood that the disappearance of horseshoe crabs would instantly cripple it. And in recent years, horseshoe crabs, particularly in Asia, have come under a number of threats: habitat loss as seawalls replace the beaches where they spawn, pollution, overfishing for use as food and bait. Horseshoe crabs bled for the biomedical use in the United States are returned to the ocean, but an estimated 50,000 also die in the process every year.
continues at link
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • VoxRat
  • wtactualf
Re: Stuff you wouldn't even think to look into
Reply #1
We routinely run that test in our lab!
"I understand Donald Trump better than many people because I really am a lot like him." - Dave Hawkins

Re: Stuff you wouldn't even think to look into
Reply #2
Maybe I should have named the thread 'Stuff you only learn on the inside.'
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

Re: Stuff you wouldn't even think to look into
Reply #3
If it bleeds we can kill it

Re: Stuff you wouldn't even think to look into
Reply #4
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
Balloons will set you free!

Re: Stuff you wouldn't even think to look into
Reply #5
$15,000 a quart!

Balloons will set you free!

Re: Stuff you wouldn't even think to look into
Reply #6
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
Quote
Horseshoe crabs bled for the biomedical use in the United States are returned to the ocean, but an estimated 50,000 also die in the process every year.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • Spode
  • I'm sorry.
Re: Stuff you wouldn't even think to look into
Reply #7
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!

https://www.youtube.com/watch?v=qlicWUDf5MM

Re: Stuff you wouldn't even think to look into
Reply #8
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
Quote
Horseshoe crabs bled for the biomedical use in the United States are returned to the ocean, but an estimated 50,000 also die in the process every year.

collateral damage
Balloons will set you free!

  • Peez
Re: Stuff you wouldn't even think to look into
Reply #9
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
If we are being technical, horseshoe crabs are not spiders either (though they are more closely related to spiders than to crabs).  Also, the blue stuff is not their blood (they don't have "blood", strictly speaking), it is their haemolymph.

Peez

Re: Stuff you wouldn't even think to look into
Reply #10
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
If we are being technical, horseshoe crabs are not spiders either (though they are more closely related to spiders than to crabs).  Also, the blue stuff is not their blood (they don't have "blood", strictly speaking), it is their haemolymph.

Peez

strictly speaking it is hemolympha heterogeneous fluid, but to the horseshoe crabs it is blood.
Balloons will set you free!

Re: Stuff you wouldn't even think to look into
Reply #11
A rose by any other name would still be blood.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • Peez
Re: Stuff you wouldn't even think to look into
Reply #12
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
If we are being technical, horseshoe crabs are not spiders either (though they are more closely related to spiders than to crabs).  Also, the blue stuff is not their blood (they don't have "blood", strictly speaking), it is their haemolymph.

Peez
If it bleeds we can kill it

They aren't killed when blood is taken. Only 1/3 of their blood is taken and they are returned to the sea. Also, they are not really crabs. Spiders!
If we are being technical, horseshoe crabs are not spiders either (though they are more closely related to spiders than to crabs).  Also, the blue stuff is not their blood (they don't have "blood", strictly speaking), it is their haemolymph.

Peez

strictly speaking it is hemolympha heterogeneous fluid, but to the horseshoe crabs it is blood.
Strictly speaking it is haemolymph (or hemolymph).
Quote
hemolymph In invertebrates with an open circulatory system, the body fluid that bathes tissues.

Campbell Biology, Second Canadian Edition, p. G-16

To horseshoe crabs haemolymph is just as much "blood" as horseshoe crabs are "crabs".

I don't have a problem calling it "blood". it is just semantics, but I found the comment about horseshoe crabs, crabs, and spiders funny.

Peez

  • VoxRat
  • wtactualf
Re: Stuff you wouldn't even think to look into
Reply #13
Interesting* little side-bar:
Limulus (i.e. horseshoe crab) hemolymph is blue because instead of our bright red, iron-containing hemoglobin to collect and deliver oxygen to tissues, they have copper-containing hemocyanin.

* well, to me, anyway.
"I understand Donald Trump better than many people because I really am a lot like him." - Dave Hawkins

Re: Stuff you wouldn't even think to look into
Reply #14
Vulcans are real
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • Peez
Re: Stuff you wouldn't even think to look into
Reply #15
A rose by any other name would still be blood.
True as far as it goes, but there are subtleties.  Animals like planarians have a little fluid between their cells, but there is no mechanism to circulate this fluid around the body.  They do have a digestive cavity with branches that extend along most of their length, water in this cavity (from the surrounding environment) helps to distribute food and other materials.  Some sea jellies ('jelly fish') have small canals that circulate sea water from a similar digestive cavity, carrying materials to other parts of the body.  Sea stars ('star fish') have a unique system that takes in sea water through a sieve and uses it to (among other things) help to distribute material through canals around their body.  Nematode worms ('roundworms') have a body cavity full of body fluid, there are no vessels or pumping organs but the animal's movements slosh the fluid around and help to distribute materials.  Ribbon worms typically have two separate body cavities connected by two vessels, there are no pumping organs and the body fluids do not circulate in any particular direction.  In arthropods like horseshoe crabs, the system of vessels is more complex and there is a pumping organ to move the fluid.  In mammals like us, the vessels form an almost completely closed system, separating the fluid outside from the specialized circulatory fluid inside.

There is no clear line between a rose and the non-rose plant that it evolved from, and there is no clear line between blood and non-blood.  However, there is a notable difference between circulatory systems that contain a specialized circulatory tissue, and those that circulate body fluid that is not distinct from the surrounding tissues.  I guess I just find that interesting. :)

Peez

  • nesb
Re: Stuff you wouldn't even think to look into
Reply #16
I will buy your spider blood for a nickel.

Re: Stuff you wouldn't even think to look into
Reply #17
Interesting* little side-bar:
Limulus (i.e. horseshoe crab) hemolymph is blue because instead of our bright red, iron-containing hemoglobin to collect and deliver oxygen to tissues, they have copper-containing hemocyanin.

* well, to me, anyway.


The same is true of the rest of phylum Arthropoda.  And phylum Mollusca too.

  • Peez
Re: Stuff you wouldn't even think to look into
Reply #18
Interesting* little side-bar:
Limulus (i.e. horseshoe crab) hemolymph is blue because instead of our bright red, iron-containing hemoglobin to collect and deliver oxygen to tissues, they have copper-containing hemocyanin.

* well, to me, anyway.


The same is true of the rest of phylum Arthropoda.  And phylum Mollusca too.
There are exceptions.  Insect haemolymph does not play a big role in transporting oxygen or carbon dioxide (their respiratory system delivers these gases directly to and from most parts of the body).  Some arthropods use haemoglobin, for example:
Quote
Respiratory protein expression in the Arthropoda generally occurs along phylogenetic lines. Hemocyanin, the blue, copper-containing respiratory protein, is found in the Chelicerata, in at least one Uniramia and in most of the Crustacea (1, 2). Hemoglobin, despite its ubiquitous appearance in both plant and animal kingdoms, is more limited in distribution amongst the Arthropoda than is He. The red, iron-containing Hb molecule has been described for only a few insects and four classes of Crustacea: the Branchiopoda, Ostracoda, Copepoda and Cirrepedia (3-7). Thus, the occurrence of Hb in an amphipod, a more advanced crustacean belonging to the class Malacostraca, is an unexpected finding. This paper describes preliminary studies on the structure and function of Hb from Cyamus scammoni, a cyamid amphipod that is an obligate ectosymbiont on the gray whale, Eschrictius robustus.
link

There are other gas transport molecules as well, like hemerythrin, found in other groups of animals.

Peez