A journey into the eyes and mind of a naturalist.

How to Make a Baby Dragon…

Insects like most multicellular life on this planet reproduce through sexual reproduction.  Simply put they exchange genetic information between two individuals.  This exchange of genetic information between two different individuals creates new genetic sequences that allows for the tremendous variation within a species and ultimately explains the diversity of life on the planet.  Species with more variation within the species will be more likely to produce offspring that will be suited for the environment.  This is not to say that every individual is best suited, quite the opposite, only a select few will have the opportunity to pass on their genes to the next generation.

The process described above is a simple idea to comprehend and is often called under the simplified term of Natural Selection; the mechanism of evolution.

 

Insects reproduce is very different ways that we are familiar with as mammals.  Many insects have very elaborate rituals to win mating rights.  Some even sacrifice their own lives for the simple opportunity to mate.  It may seem like a cruel world but the drive to pass on one’s genes to the next generation makes organisms (human or otherwise) do some extreme behavior.

 

Dragonflies have a rather unusual method of mating.  The male has claspers on the end of his abdomen that he uses to clasp onto the perspective female’s head.  This love grip allows the female to conjugate with the male using her elongated abdomen.  The position may seem odd but it allows the pair to maintain flight ability throughout the mating process.  Together they fly through the air avoiding the hazards that lurk by perching on the ground or vegetation.

The photo above clearly illustrates how the conjugated mating position allows for sufficient movement and clearance of both sets of wings.  I found this pair resting right outside my front door late last summer.

The photo above is a detail of the male claspers grasping the female by the head.  The morphology of the claspers prevents damage to the sensitive eyes of the female.  I think this could be the dragonfly equivalent of a hug.

When the mating is complete the female will visit a nearby water source where she will lay her fertilized eggs just below the surface of the water on aquatic vegetation or debris.  The eggs will hatch into tiny nymphs and will spend up to several years developing underwater before emerging as an adult dragonfly on a cool summer night.

I saw my last dragonfly of the season on November 7, 2011.  This was an extremely late date to see dragonflies flying around in central Minnesota!   Without flying insects to eat adult dragonflies ultimately succumb to the elements or loss of food.  Only those who were able to pass on their genes will influence the population of dragonflies the following summer.  Without sexual reproduction we would not have the tremendous diversity of life on this planet.  Without a diverse genetic library within a species there cannot be success for that species no matter where it lives.  Without the variation it is genetically destine for extinction.  That genetic threshold is difficult to identify and depends largely on the species.   One must ask themselves if many of our “endangered species” are already effectively extinct from a genetic perspective.  Loss of a single individual can have dramatic effects in a small population from a genetic perspective.

What is the purpose of conservation?  Are we conserving the world for humans or for all life?

 

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