|Back to Back Issues Page|
The Incredible Egg
April 30, 2018
You would think we would learn.
Never leave the trash out when you take off for 30 minutes or so.
The girls were having some fun.
Akita was right in the middle of it all, she growled at bit and left the scene.
You can see Snickers to the
I managed a picture of the debris field, I couldn't capture them in the act. though I did see them in the middle of the carnage.
All one can do is smile and clean up the mess.
I think it is safe to say that April, 2018 is going down as the coldest April recorded in Kent County, MI.
May, please be normal.
Sadly, Michigan records indicate a cooler summer when we have a cold April.
We survived, didn't we?
My Karen doesn't think so right now.
She is a battling Conjunctivitis for the second time this month.
That's right, good OLE fashioned 'Pink Eye'.
Getting drops in her eyes is a real struggle.
I think this is why it returned, didn't finish the drops.
Yolanda and I have managed to stay clear of it so far.
Out door tasks are slowly getting worked on, which means the 'Honey Do' lost is now on the back burner (Darn it).
Birds continue to be the center of attraction.
Did I ever tell you I love birds?
While digging in the dirt pie (filling pots), I unearthed this toad.
Still in a hibernation state, but not a frozen hockey puck like in past years.
I replaced it so it can warm up naturally.
(Downy Woodpecker at suet log.)
We turn the page on the calendar.
Gardening gets into full swing this month.
This applies to folks in frost risk regions.......
Don't be in a big hurry to plant tender annuals.
Not just for frost, but allow the soil to warm up a bit.
Planting tomatoes and peppers in cool soil stunts, and sets back the growth of these hot weather plants.
A new month also means it is time to clean bird feeders and water sources.
I like the first of the month, it is easy to remember.
As weather warms, a good, deep, cleaning is in order.
Remember to rinse and dry feeders before filling and putting them back out.
May is also the month I anticipate the arrival or Orioles and Ruby-throated hummingbirds, along with several other migratory birds.
The First of May.
Do you remember May Day?
It was something special for children everywhere.
Making a basket (often from paper we would color, cut and tape into a basket), and picking flowers to give to your mom or grandma.
Sometimes the basket was full of dandelions and violets, but mom (grandma), didn't seem to mind one bit.
Some years there would be paper flowers to fill the basket.
What ever happened to "May Day"?
Another lengthy, but i think informative letter.
The Incredible Egg.
In the past I discussed a bit on Bird Romance and courtships.
As well as territories, bird love, and nests.
Today, I'm going into more detail on bird eggs.
How they are made, what's in an egg and more.
Here is a tidbit for you.......
Oology, is the branch of ornithology that deals with the anatomy and physiology of eggs as well as the size, shape, color and other characteristics.
Yep, there is a name for just about everything.
Don't you feel smarter already :-)
The Kiss .....
After mating, inside the female, sperm may wait several weeks or swim up a tube called the oviduct, at the end of which there is an ovum.
If the ovum is mature, it's already equipped with yolk, the yellow part of the future egg.
The sperm may now fertilize the ovum by penetrating it and uniting the two reproductive-cells' genetic material.
Fertilization doesn't necessarily take place soon after mating; domestic chickens and turkeys can produce fertile eggs seventy days after copulation.
After fertilization, the ovum with its yolk begins its own journey down the oviduct, a process lasting about 24 hours.
During the first three or four hours, moving along the way, the albumen (egg white) is added around the ovum and its yolk.
The picture above is a bird ovary and you can see the different stages of the yolk and ovum as it develops.
The yolk will serve as food material for the developing chick.
The white will mainly keep the yolk from drying out, and will give the yolk physical support.
A Side Bar:
The yolk size varies from bird to bird.
The more independent the hatchling is, the larger the yolk will be.
Geese, ducks, and chickens, have a larger yoke per egg size than birds hatched helpless.
(Dove Nest.) Now the future egg slows to about 40 percent of its earlier speed, and membranes are added around the yolk and egg white.
Finally the shell is put in place, taking 19 to 20 hours.
The egg them moves to the uterus, or shell gland, where the calcareous shell is added and, in some birds, pigment is added in characteristic patterns.
The shell is mostly composed of the mineral called calcium carbonate, which has the same chemical formula as limestone.
(No wonder egg shells are so hard and brittle.)
Pretty amazing that all of this is built up around the yolk in a 24 hour period.
The egg then passes into the vagina and cloaca (klō-ˈā-kə), for laying.
I would call that one efficient, and hard working assembly line.
Technically speaking, eggs are single cells, even though we normally think of cells as too small to see with our naked eyes.
In fact, eggs are the largest cells known in the animal kingdom.
They range in size from tiny ones produced by hummingbirds (0.006 oz, or 0.2 gram), to nearly 20LBs (9 kg), laid by the Elephant bird of Madagascar, which is now extinct, but was known by primitive humans.
The Components Of An Egg:
An egg has four basic structures.
The yolk and its associated membranes, the germinal disc, the albumen (white), and the shell and its associated membranes.
Each component performs specific functions in the development of the embryo.
The yolk is the main source of nutrition for the embryo.
The fat gives yolk its yellow color.
The more fat contained in the yolk, the darker the yellow.
Now pay attention ..............
Surrounding the yolk are four membranes that keep it intact and in contact with, but separate from, the albumen.
After the egg has been fertilized and incubation starts, a system of blood vessels develops within these yolk membranes, which completely surround the yolk and carry nutrition to the embryo.
On the surface of the yolk is the germinal disc, a small disc of cytoplasm containing the DNA nucleus of the female cell, or ova.
You need a microscope to see the nucleus, but you can see the germinal disc with the naked eye.
It appears on the surface of the yolk as a white dot.
“If the egg is fertile, the dot is called a 'blastoderm'.
If it is not fertile, it.s called a 'blastodisc'.
The blastoderm contains the genetic material necessary to develop into offspring of the parent birds.
(Purple Martin Nest.)
The albumen is the white or clear part of the egg that surrounds the yolk.
Made up mostly of protein, it also contains globulins, which provide immunity from disease.
The albumen feeds the developing embryo with water and protein.
When the chick is ready to hatch, the albumen acts as a lubricant to help the chick turn, push and struggle to free itself from the egg.
Albumen consists of thick viscous forms and thin, watery forms.
A layer of watery albumen surrounds the yolk, and a more viscous layer of albumen is in contact with the watery layer.
A third watery layer of albumen is in contact with the shell’s inner membrane.
A dense layer of albumen called the chalaziferous layer is in direct contact with the outer yolk membrane.
This is so fascinating .....................
An extension of this layer forms the chalazae, twisted strands of thick albumen that connect to the shell membrane at each end of the egg.
The chalazae stabilizes the yolk and embryo in the center of the egg within the albumen layers.
The chalazae is much like a shock absorber that keeps the yolk and embryo stable.
The chalazae become twisted as the egg is turned during incubation.
(These invisible strands are what make it difficult to separate the white from the yolk when recipes call for whites or yolks.)
(Northern Cardinal Nest.)
The hard outer surface of a bird egg is the shell:
It provides protection and structure to house the embryo.
The shell contains pores to allow for transpiration of water through the shell.
The shell consists of three layers; the outermost layer is the cuticle.
Beneath the cuticle is the calcium carbonate layer called the testa, and the innermost layer is the mammillary layer.
The cuticle consists of dried mucus laid down by the uterus and serves to regulate evaporation of moisture and to protect the embryo from bacterial infection.
The testa is the layer that makes up most of the eggshell structure and provides calcium to the growing chick.
It is also the layer that contains the pigments if the egg is colored.
The mammillary layer is in direct contact with the shell membranes and is the foundation for the testa.
Two membranes lie directly beneath the shell: the inner shell membrane and the outer shell membrane.
At the blunt end of the egg, the two membranes separate, forming a space between them called the air cell.
The air cell is formed after the egg is laid and cools.
The outer shell membrane adheres to the mammillary layer of the shell.
The inner shell membrane covers the liquid inside the egg.
"Creation", has made it possible for birds to lay from a single egg to 20 or more and have them sit dormant for a period of time until incubation begins.
This way all the eggs can hatch within hours of each other.
Some birds do lay and hatch on an every other day schedule, however.
I hope this gives you an idea a on what makes up a bird's egg and how it is made.
God's work is so impressive, and a special process don't you think?
Well, it is time to fly for now.
Before I go, here is your positive thought for the week.
“Worry and fear cannot live in the same space with hope and action.
When you stand on faith and take positive action,
You evict worry and fear.”
Now the word of God.
"There is no fear in love;
But perfect love casts out fear,
Because fear involves punishment,
And the one who fears is not perfected in love".
1 John 4:18
"Treat the earth well:
It was not given to you by your parents,
It was loaned to you by your children.
We do not inherit the Earth from our ancestors,
We borrow it from our Children."
Ancient Indian Proverb.
Your friend indeed,
Better yet, have them sign up so they can receive their own letters.
|Back to Back Issues Page|