Other Parts

Interior parts of animals are somethings that may be forgotten about.  People go through biology classes to see the interiors, yet do we really think about them?

Do we really realize that all animals have similar organs to ourselves?  Do we stop to think about that?

During my last several posts about horseshoe crabs, I made a list of the body parts I haven’t talked about and usually don’t.

They have: a prosoma (top part), opisthosoma (abdomen), carapace (covering), hinge, chelicera, gnathobase, chilarium, genital operculum, gill opercula, gills, anus, cardiac, extracardiac, and subopthalmic. And I may be missing one or two.

Horseshoe crabs breathe through their gills like fish do yet their gills are on the underside of their bodies.  One can only see them when you pick one up and turn it over. They looked like layered fans.  Their gills allow them to breathe, unlike fish, both in water and on land.

And yes, they have a cardiac system to move that blue blood around.  (See earlier post). One of the main criticisms of their bleeding by pharmaceutical companies is that they insert the needles near the hinge on the horseshoe crab which is also right where their main cardiac is located.  This would be like having a large needle jammed in your neck or chest and your blood sucked out.  We don’t know for sure if they feel pain but they must if they have a brain and neurological system.

Thoughts?

 

 

Mommy and Daddy Crabs

Talking about male/ female crabs and how the horseshoe eggs come to be can be interesting and sometimes awkward depending on the audience.

Unlike the male fiddler crabs that have the large claw to attract females, male horseshoe crabs mate a completely different way.

As mentioned briefly before, females are usually larger and males smaller.  This is the first clue in identification.  If this is not clear, the next best way to identify the crab, if at all possible, is through their legs.

Horseshoe crabs have six sets of legs.  Only the back five are used for them to walk and to eat.  The front set, closest to the top of the shell or carapace, are called pedipalps, palps, or palpi. Pedi comes from the Latin for “foot” and palp from the Latin for “touching”.  On the females, these look like their walking legs.  On the males, they can be described as looking like mittens, boxing gloves, large claws, or large pincers.

Females give off pheromones to attract the males when they, the females, arrive on shore.  The males are usually waiting for the females to come up.

The males use these pedipalps to hold onto the back of the female crab on an area known as the opisthosoma.  This is the back part of the crab right before the telson.  They hang on very tightly.  Waiting.

If you, the reader, ever have the chance to observe the horseshoe crabs mating, watch carefully.  They are silent and strong and follow along with the currents one may or may not be aware of.

More than one male horseshoe crab can follow and fertilize just one female’s eggs.  One female can lay an estimated 9,000 to 90,000 eggs.  She may lay them in one hole or may create more than one hole.  The male or males follow along, attached or not, to fertilize the eggs.

Once the female lays her eggs, the eggs will be on their own.  The female leaves.

Most people find it shocking that the horseshoe crabs would go through all of this trouble and then leave their eggs. Yet if one thinks about it, they are not the only species that do this.  The animals humans look to like frogs, turtles, and fish do this as well.

The eyes (and telson) have it…..

People are terrified of the horseshoe crab’s telson, or tail.  My reaction is: really? The tail is used to help the horseshoe crab get around in the water, like a rudder on a boat, and they also use it to flip themselves over in the water should they be turned over.  However, it is very difficult for the horseshoe crab to do this on land.  Most of the time they need help, human help, to flip over or risk being eaten by birds and other wildlife.

Another interesting fact I recently learned about the horseshoe crab’s tail: there are photoreceptors on the tail.

What is a photoreceptor?  A photoreceptor is basically a cell that responds to light.

Horseshoe crabs also have 9 eyes and their vision, as we understand it, is very poor. However, they use their eyes and the photoreceptors to navigate their environment.

This gives new meaning to the expression “eyes behind your head”.

 

 

 

#TeachbackThursday Limulidae

Did I get your attention?

Do you know what Limulidae are?  They are important to you.

I saw a pair mating today.  I showed about thirty or forty other people the same pair today. I made it clear I wasn’t touching them and we were just looking.  They were moving slightly.  They were trying to burrow in the peat to stay cool from the warming sun.  They came up high on the sandy shore, mating, burying their eggs.

They are older than dinosaurs.  They are living fossils.  They are feared because of the way they look.  People abuse them.  People use them for bait.  They are somewhere between threatened and endangered.

They do nothing to us.  They are gentle.  I can stick my hand where their legs are and they will do nothing to me or anyone else.

Yet we also need them.  We need them for their blue, copper-filled blood.  (Our blood is red from the hemoglobin.)  We need them to aerate the ocean bottoms for us and to control populations of smaller creatures.

Science uses them, collects their blood, to help identify bacteria in liquids and to add to IV (saline) bags in the hospital.  They often do not survive having their blood being collected.

Barnacles like to tag along for the ride on their shells.  This is a symbiotic relationship.  A symbiotic relationship is where nobody in a relationship is hurt.  (Think sharks and the feeder fish that swim alongside eating the leftover food bits.)

They use their tail for navigation and to flip themselves over if they get stuck on their back.  It doesn’t hurt anything or anyone.

They lay thousands of eggs but only a fraction may make it to adulthood.

It breaks my heart when people tell me they see people abusing these animals.  They are so gentle.

This is part of what I do.  I show people animals and places they may not know about.  I spend a lot of hours volunteering during the late spring giving tours of a local salt tidal marsh to local fourth grade students and their adult counterparts.  Most people who come down, adults included, have no idea what they drive past each day and how vital it is to the area in which we live.

The scary part is many people haven’t been learning what an ecosystem is and why it is important.

What am I teaching back? Learn about things and animals that scare you or you don’t know about.  Go out into the community.  Go out into the world.  Find out why things are important.  Explore.  Learn.  Grow.  Share.

I’m there because I love it, I love the horseshoe crabs, I love the fiddler crabs.  I love the smell.  I love the view.  I just love it and don’t want to see it disappear.

Long live the Limulidae!

Book review: “Firegirl” by Tony Abbott

One of the first things you learn while working in public service is that there is much more behind the headlines. Firegirl is one of those books that talks about the “after” and the rumors, gossip, and innuendo that follow people who are visibly changed by what has happened to them.

A powerful coming of age story and must-read for those who facilitate dialogue about community and societal change.

This is ideal for the tween and teen age groups and talks about the choice of following your consciousness or following the group. It also addresses how people show their true colors when confronted with someone who makes them uncomfortable.

Another must read by Mr. Abbott!

Talking about…..

I’m exhausted right now while I write this. We had quite a scare here earlier this evening, I will write more about it later. Some time out with an art opening, an outdoor music fest, and some old and new friends helped.

This morning I had a chance to share at a networking meeting what I do. It’s August, only a few people were there, and all of them I have met before. I talked about some of my clients and what I do to help them, the conversations I’ve had with parents, and some of the more heartbreaking times I’ve tried to help people but it doesn’t always work. I’m grateful for this chance because it is usually something I don’t get a chance to do.

One story I related, and as of right now I don’t have any follow-up, was a phone call I received from a woman whose son was in the process of having an IEP and the school district wanted to label him special needs because he wasn’t reading at 4, in preschool. Someone had given her my number, thank you if the person is reading this, and I spent two hours on the phone with her. She told me they were concerned because he wasn’t reading and that he needed to be ready for testing in Kindergarten. She had no idea that you are allowed to have someone with you, attorney or otherwise, for the IEP meeting and that you are allowed to record them. I told her to check the state’s statutes and laws.

We discussed the labeling aspect: pros and cons.

We discussed Michael Gurian and I recommended that she read his works. His books have been hugely helpful to me over the years in understanding and dealing with people not only academically but professionally as well.

We discussed how even if you learn to read at 4 or 14, everyone is at the same level by the time they are 18 years-old. Yes,some people never learn to full read and are functionally illiterate, and I know people in this situation and have worked with them and how it is heartbreaking. Yet the stress of having to read at 4…..

I wonder how she is doing. If you are reading this, please let me know.