I am sure that when you and your family gathered around the Thanksgiving table this year you don’t spend all your time talking about birds, migration and how all of that ties into the dark and light meat of the Thanksgiving turkey, like my house.
Ok, I will admit, it’s all my fault. I can’t help myself when someone makes an offhand comment about liking or disliking dark meat or light meat. Or someone might express an interest in having just the breast meat. When I hear this, I feel obligated to ask everyone gathered one simple question. “Do you ever wonder why turkeys have light meat and dark meat.” The answers I get are just blank stares. Of course no one is thinking about this. It’s just me who thinks about these ridiculous things.
But these are also the things that I like to think about. So here is a brief explanation for you to bring up around your Thanksgiving table next year. What we call meat, no matter if dark or light are the birds muscles. Muscles are meat. All meat produces some kind of movement. There are many different kinds of movement depending upon what the bird needs. Birds such as turkeys and chickens spend nearly all of their time walking on the ground looking and scratching around for food. They are not migratory birds. The muscles in their legs are adapted for constant use and don’t fatigue easily.
The large leg muscles are made up of strands of red fibers that contain an abundance of fat and sugars, which are the fuel for the muscle. These muscles are also good at working with reduced oxygen requirements. These birds can walk around all day and still have enough energy and speed to run away from predators. This is the reason there is so much meat on the legs of turkeys and chickens.
The reason birds can fly are partially because of large breast muscles. In fact, in turkeys and chickens the breast muscle makes up 1/5th of the birds entire weight. In some species such as hummingbirds the breast muscle makes up 1/4 or 25 percent of the birds entire weight. It is composed to two muscles, the pectoralis (downward wing movement) and the supracoracoideus (upward wing movement) muscles. This is why the breast muscle is so bulky and thick.
Like most muscles, the breast or flight muscles act in opposite pairs or antagonistically. When one contacts the other relaxes and produces smooth or fluid movement necessary for smooth wing beats. Birds such as turkeys don’t fly long distance. They don’t migrate great distances. So the breast muscle is different from the long haul leg muscles and looks different.
The breast muscle of the turkey is adapted for short duration explosive bursts of power to carry it quickly away when a predator approaches. Turkeys can fly upwards of 55 miles per hour but not for long periods of time. These muscles don’t have much oils and sugars and works mostly on oxygen and appears light thus they are white in appearance.
So, armed with information, what do you think a the breast meat of a migratory duck would be? Light meat or dark? Ok, I think you are getting the hang of this thing.
In nature, nothing is haphazard or “just because”. There is a reason and explanation for everything. You just need to sit down and get into the meat of it. Until next time…
Stan Tekiela is an author / naturalist and wildlife photographer who travels the US to study and photograph wildlife. He can be followed at facebook.com and twitter.com or you can contact him via his web page at www.naturesmart.com.