Posts Tagged With: Evolution

#Evolution of #Flight by #Chiroptera (aka #Bats)

Big-eared-townsend-fledermaus

This is some of the research that contributed to the recently released Darwin’s Paradox: An international science mysteryhttp://amzn.to/2k8qJgi. Bats have a major role in this books, also the people who try to protect them when they become a target of fearful people during the pandemic.

An important principle of evolution is that evolution does not plan. There is no such thing as a species evolving in a direction that is not superior to the status quo just to be better prepared for some eventual benefit later.

This is important when thinking about flight, or any evolutionary change that makes use of several systems (such as the skeletal system, cardiovascular system, and the respiratory system), or which requires significant anatomical modifications. Both of these are true for flight.

1024px-Darwin's_finches_by_Gould

While speciation, based on size and color (canis and felis) or beaks (Darwin’s finches), can be understood by a few, small genetic changes, the evolution of flight is more complex. However, in spite of the complexity, flight has evolved at least four independent times: insects, pterosaurs, bats, and birds.

Homology

Flight requires both the development of wings and changes to cardiorespiratory systems to support the short-term effort required for aerial takeoff.

Now, from the no planning principle, we know that in the millennia before flight is achieved, the intermediate changes must be an improvement at every step of the way. In the case of flight, there are two major theories for an evolutionary path to flight.

Domestic_Pigeon_Flock

The first path to flight (ground up) assumes an animal that lives on the ground and evolves to run faster building up their cadriorespiratory endurance and uses their hands to catch prey expanding the area of their hands. Over time this animal benefits from hopping and gliding and finally true flight. This seems to be a good theory for birds.

Quetzalcoatlus07

The second path to flight (height down) assumes an arboreal animal that lives in the trees and first jumps down on prey, and eventually glides, and finally develops true flight. This seems to be a good theory for pterosaurs.

In the case of chiroptera (bats), it could have gone either way. There are bats that run along the ground suggesting ground up and those that climb trees suggesting height down.

In either case, bats have successfully populated all continents except Antarctica. They represent 20% of all mammal species, second only to rodents.

pub-shot-dp-13-cropped

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Father’s Day – anachronism, atavism, or reason to celebrate?

Father's Day

The Last Father’s Day?

There are two theories about fathers. One represented by Women After All by Melvin Konner believes that at best fathers are unnecessary, but at worst they are a threat to civilization and humanity. The alternate theory represented by Do Fathers Matter? by Paul Raeburn expounds that fathers are important and salvation for the futures

A brief digression. The fable of regret, dread, and fantasy.

800px-Kornnatter

Long ago there lived a very happy snake. Each day the snake awoke afresh with no memory of any day before. The snake was happy.

One day the snake met a wizard who granted the snake three wishes. With each day new, the snake had never wanted anything.

But on this day it looked around at man, “Like man I wish to remember the past.” As the snake recalled its past life, it experienced regret for the first time, for mistakes, errors, and missed opportunities.

It had so much regret, it wished to be able to think of the future and plan. With its second wish, the snake experienced dread and fear.

With this broad purview, the snake made its final wish, “I wish to be able to fantasize and escape my miserable life.”

Thus the snake had learned the secret of true misery: Collect regrets from the past, use them to fill the future with dread, and, most of all, ignore the present.

Fathers

Do Fathers Matter? by Paul Raeburn is like the snake before the three wishes. Raeburn reviews evolutionary biology and history of fatherhood with a snakelike focus on a father’s contribution during each phase of reproduction: pre-conception, conception, during pregnancy, and during the various post-natal stages. At each point he shows the importance of the father’s participation. Like the snake, each day is unique and wonderful.

As reported by Raeburn, parthenogenesis is impossible. Current science shows that both males and females contribute unique and vital genetic material, so a new life is not possible with contributions from both sexes.

Each day is Happy Father’s Day.

Women After All by Melvin Konner personifies the miserable snake after the three wishes.

Konner reaches back to the evolution of sex noting that life started with only females. With regret he reports the evolution of a second sex (males), but with a more cheerful note, he reports that there are some examples of species reverting to the single sex (female) mode.

He shows that primate females (including humans) were usually in charge or equal, with the exception of the last few thousand years. These recent millennia were marked by brutal female subjugation, violence, and rape. For several sickening chapters, Konner shows that sex trafficking, slavery, and rape is universally practiced.

Konner mixes this regretful past with the assurance that future science will solve all the problems with parthenogenesis, and in a few decades male humans will be superfluous. Bottom line: Men should dread the future where they will be unnecessary.

The message seems to be that fathers need to straighten out or be consigned to a life of regret and dread as they are phased out.

Today is Happy Father’s Day, enjoy it while you can.

Be careful what you wish for.

Categories: Father's Day | Tags: , , , | Leave a comment

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