1610: The Starry Messenger

The invention of the telescope by Dutch spectacle makers in 1608, and vastly improved upon by Galileo two years later, provided the tool for some of the most revolutionary and groundbreaking discoveries in the history of science.

Published by Galileo Galilei on March 13, 1610, Sidereus Nuncius (or Starry Messenger) revealed to the world Galileo’s observations as he view the night sky through his improved telescope.  These new revelations changed how we viewed the composition of the universe and our place among the cosmos and heavens.  Among these observations included: craters and mountains on the moon, additional stars in the night sky, and the discovery of four of Jupiter’s moons.

The publication of this book began the process of upending the long held ideas of Aristotelian cosmology and Ptolemaic astronomy by providing evidence for heliocentrocism, which was at the time in direct conflict with Christian theology.

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A Spirited Attack on the Holy Spirit

holy-spirit-unterlinden-14thThe Holy Spirit is an elusive enigma. The Holy Spirit – one of three different yet same incarnations of the one true God (dwell on that paradoxical nonsense for a moment) – is a central figure in the Christian Holy Trinity; it is an entity which all Christians are said to possess.  Yet, it’s presence and physical properties conveniently and mysteriously escape the detection of modern scientific methods and instruments.  It reminds me of the dragon story in Carl Sagan’s classic, The Demon-Haunted World – Science as a Candle in the Dark.  To paraphrase the story:

Imagine I say to you that I have a real live dragon in my garage – surely you’d want to see it for yourself. What an opportunity, you think, to see a dragon, of which have been the stories of legends over the centuries, but has left no evidence.

“Show me,” you say, and I lead you to my garage.  You look inside and see some bags of sand, cans of spray paint, some interesting goggles, and other items in my garage, but no dragon.

“Where’s the dragon?” you ask.

“Right here.” I reply, waving vaguely.  “I neglected to mention the dragon is invisible.”

Hmm, you think.  You propose spreading some sand on the floor of the garage to capture the dragon’s footprints.

“Good idea.” I say, “but this is also a floating dragon.”

Well then you’ll use those infrared sensor googles over there to detect the invisible fire.

“Good idea, but the invisible fire is also heatless.”

Ok, so you’ll spray paint the dragon to make it visible.

“Good idea, but it’s an incorporeal dragon and the paint won’t stick.  And so on.  And so on. And so on. I counter every physical test you propose with a special explanation of why it won’t work.

Now let me ask you this.  What is the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there’s no way to disprove my dragon proposition, no conceivable experiment that would count against it, what does it mean to say that my dragon exists?

Maybe, the only thing that you have really learned from my insistence that there’s a dragon in my garage is that there is something funny going on inside my head. Maybe you’d also wonder, if there are no physical tests that apply – nothing to show its mass, nothing to show its heat, nothing to show its chemistry – then what convinced me of the dragon’s existence in the first place?

The analogy between my dragon and the Holy Spirit should be clear at this point.  If the Holy Spirit resides within us, then we should be able to test for it.  We should, for example, be able to turn to the index of any biology textbook and reference the Holy Spirit just like we can for proteins, enzymes, neurotransmitters, DNA, ATP, lipids, the biochemistry of muscle fibers, the chemistry and structure of cells, the mechanisms of the nervous system, and on and on and on.

Until we can have any verifiable evidence of its existence it is safe to say that the Holy Spirit is imaginary.


Further reading: Science as a Candle in the Dark by Carl Sagan

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The Origins of Religion Part 5: The Benefits of Early Religion

We’ve seen that religion provided many beneficial functions for prescientific peoples such as providing a completed – even if inaccurate – a sense of cause and effect for phenomena they did not and at the time could not understand, and by providing moral and social order and stability at the dawn of human civilization. These functions were enabled and reinforced by performing rituals that supposedly evoked the powers of the supernatural.

Aside from those main functions religion also provided other supplemental benefits to our ancestors. In hunter-gatherer bands religion provided a rudimentary form of medicine, group identity, and prestige to the shamans and warriors who labored in the name of their gods. Many times religion provided legitimacy to these shamans and warrior rulers, increasing confidence from the group in their abilities and reducing strife within the group. As humans made the transition from hunter-gatherer bands to sedentary tribes, chiefdoms, and eventually city-states, religion provided an increasing role as a source of national identity for the group. The writings of the Ancient Egyptians, Greeks, the Hebrew Bible, and many other early religious sources clearly illustrate this point.

On the level of the individual, religion allowed people to have the perception of a greater sense of control over of their lives. An adequate amount of rainfall is necessary for crops to grow, but the amount of rain in a certain area during a given time is out of people’s control. By performing rituals to their gods, people at least felt like they had a sense of control over the weather, even if they didn’t. The same was true for warfare, diseases, and other things that may have been out of people’s control. In an uncertain and incomprehensible world, this added sense of control provided comfort, hope, and reassurance in many of its beliefs, for instance the comfort gained by the belief in the afterlife.

Religion appears to have been a cultural evolutionary necessity in allowing the transition from hunter-gatherer bands to modern nation states. Unfortunately it is a persistent vestige of the dawn of civilization that now creates more problems in the modern world than the superficial benefits that it currently provides.


Further reading: The World Until Yesterday by Jared Diamond; The Evolution of God by Robert Wright

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The Origins of Religion Part 4: Social Order and Stability

The need for social order and stability became an urgent and novel problem for large groups of people after the invention of agriculture. Prior to the invention of agriculture, people lived in bands numbering a few dozen up to no more than a few hundred people, where everybody knew everybody else and decisions could be made collectively as a group. Once agriculture provided for surplus food production bands could increase in size from dozens of people to tens or hundreds of thousands of people. This was the most critical move that humanity has ever undertaken – removing us from our hunter-gather environment which human and prehuman ancestors evolved in for hundreds of thousands of years to placing us in large city-state environments with larger populations, divisions of labor, and everything else that came along with an agricultural society. Once of the most pressing problems then, was how to get people to cooperate with each other; in other words how not to steal possessions and women from people you didn’t know and were never going to see again and not to fight and kill those same people. Religion appears to have provided the earliest solution to this problem by coding for behaviors that their gods either pTen Commandmentspunished or rewarded.

The patterns of ancient religions are illuminating. While the god and mythologies are largely random and a product of cultural drift, the practical themes to the functioning of society are more consistent – themes such as obeying the religion, not stealing, and not killing member of one’s own religion. Nearly all ancient religions codified these teachings in one way or another as most are familiar with the Ten Commandments of Judaism and Christianity.

Another way that religion provided social stability is that it worked to reduce anxiety and provided people with comfort in the face of uncertainty. For instance, starvation was serious concern at the dawn of agriculture when crop yields depended on the weather. A hurricane could wipe out most of the crops or a drought could kill most of the crops. When people have done everything in their control, the next step is to turn to religion – to resort to rituals, prayers, sacrifices to the gods, reading and interpreting omens, and so on. Although these actions are scientifically worthless, they at least gave people who knew nothing about science the feeling that they were in charge, in control, and made them feel less anxious and more comfortable about their futures. This function of providing comfort also applied to death, in providing an explanation for death, hope in the form of a pleasant afterlife, or a sense of justice that people who have wronged you in this life will be punished in their afterlife.

The origins of religion are quite different from the modern, institutionalized religion of today.  Putting all of these components and functions together in order to understand the benefits of religion will be the subject of the last part of this series.


Further reading: The World Until Yesterday by Jared Diamond; The Evolution of God by Robert Wright


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The Origins of Religion Part 3: Rituals

It seems evident through the discoveries of anthropologists that early human hunter-gather societies used primitive religion as a means of explaining and understanding phenomenon in the natural world.  They did this by invoking supernatural beings and spirits and attributing human personality characteristics to them.  If these supernatural beings had the power to alter and influence worldly events and behaved similarly to humans, it’s logic to assume that they could be influenced by human actions as well.  Actions performed in order to appease these supernatural beings became ritualized.

Rituals were used extensively as Rites of Passage that mark a persons passage through certain cycles of life – birth, manhood, marriage, and death.  Rituals are not a unique human trait and it is very likely that ancient rituals came about as an outgrowth of animal rituals fAncient ritualor mating, dominance, and the like – much like a bee’s intricate dance or a birds song.  In any case, death may have been the most influential rite of passage to early humans and ancestor worship was particularly common among early humans.  Rituals involving the death of a person have been observed even among the Neanderthals dating as far back as 40,000 years ago.  These rituals were used as a form of communication with the spirits of the dead and the afterlife.

That rituals – patterns of behavior – are used as communication devices provided the means to communicate with spirits in all sorts of realms in addition to the realm of the afterlife.  The spirits of the wind, the forest, the sea, and so on could be influenced by and communicated to through ritualized behavior.  Ritual also worked to bring cohesion, trust, and order to the social group.  Following the agricultural revolution, as human societies began to grow in size and complexity, exiting the hunter-gather state and forming chiefdom’s and eventually city-states, religion served the function of maintaining order, establishing social norms, and providing social control and divine legitimacy to the ruling elite.  It is these functions to which we turn our attention to next.


Further reading: Breaking the Spell by Daniel Dennett; The Evolution of God by Robert Wright


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The Origins of Religion Part 2: Superstition and Spirituality

Having a complete sense of cause and effect helps people navigate through the world by being able to make accurate predictions as to the effects of actions and events.  In some cases, such as explaining cycling of the heavenly bodies, the changing seasons, harmful diseases, and even the movements and actions of living beings, early humans living in a prescientific world couldn’t complete their sense of cause and effect through natural processes; instead they overcame that deficiency by evoking superstitions – a belief in supernatural causality.

Early religions personified these supernatural agents as souls, spirits, and eventually gods and these agents caused, intervened, and acted on worldly events.  In order to make these supernatural agents more meaningful and memorable a multitude of stories were built up around them.  Before the invention of writing, the stories of souls, spirits, gods and their deeds were passed down from generation to generation orally.  Eventually some of those stories were written down.  It is anHorus exercise in futility to go through all of the gods that humanity has created since there have been tens of thousands of them.  We know today, of course, that all of them are imaginary.  As Richard Dawkins points out: “We are all atheists about most of the gods that humanity has ever believed in.  Some of us just go one god further.”

Superstition was supplemented by spirituality – a connection with the divine.  A connection with the divine was doubtless perceived through altered states of consciousness in states of dreams, hallucinations, and trances.  These altered states of consciousness helped lead to the widespread belief in the duel nature of beings – that the mind was separate from and could exist independently of the body.  This further implied the existence of a soul or spirit as an animating force that could be applied to people, and by logic also extended to other animals and plants, and even objects such as rocks, rivers, clouds and stars.

Sir Edward Tylor, the father of modern social anthropology, called this belief that nature had an animating soul or spirit animism, vaulting the hitherto obscure term to prominence in his 1871 book Primitive Culture.  He believed that animism was the first phase in the evolution of religions and argued that people originally used religion to explain phenomena in the natural world.  According to Tylor, animism easily answers many questions early humans had such as what happens when we dream.  Souls wandering out of the body in some cases, or neighboring souls visiting the body in other cases provided a plausible answer.

Invoking souls, spirits, and eventually gods allowed early humans to complete their sense of cause and effect about how the world worked.  This is not to say their sense of cause and effect was correct, but it was now at least complete.  With a complete set of beliefs about how the world supposedly worked, the next step was to try to begin to cooperate with and influence the world in order to achieve desired goals.  The methods thought to accomplish this task include rituals, prayer, and other means which we will look at next.


Further reading:  The Dominate Animal by Paul and Anne Ehrlich; Breaking the Spell by Daniel Dennett; The God Delusion by Richard Dawkins; The Evolution of God by Robert Wright

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The Origins of Religion Part 1: Cause and Effect

Religion is one of the most prevalent and influential aspects of human civilization and culture.  Nearly all societies across the globe in every recorded era have some sort of religion, worship a god (or gods), or possess a set of religious beliefs.  People pour a great deal of time and energy into their religion with some willingly giving their life in the name of their sacred religion.  However, while nearly all groups of people have invented gods and the religious stories revolving around their gods, perhaps the most striking feature of religion is that these stories are wildly different.  Consider the differing religious gods, stories, and teachings of the Norse, Greek, Roman, Persians, Hindus, Egyptians, Aztecs, Babylonians, Chinese, Indians, Christians, and Jews – to name a few of the thousands of religions and gods known through history.  These religions and gods have a few similarities, such as creation stories and stories about what happens after death, but their particulars are all very different.  So which religion is right, if any?  And how did these stories and gods come into existence?  A systematic inquiry into the evolutionary origins of religion can elucidate some understanding to those questions – and many others – regarding religion.Ancient Religion

Religion is a worldview and can be described as a set of beliefs about the causes, nature, and purpose of the universe.  Since human beings, and to a lesser extent all other animals, navigate the world by developing a set of cause and effect it would have been important for our ancestors to develop a sense of understanding about how our world worked.  Animals develop their sense of cause and effect in order to carry out tasks essential to their lives, such as where to find food, how to get mates, and how to avoid danger.  With the evolution of human intellect – the ability to have abstract ideas, to communicate those ideas through language, and to remember things from the past – people are able to perceive more about the world than other animals and therefore have a greater sense of cause and effect. This also meant we could ask more questions and attempt to answer them the best that we could given our knowledge and understanding of the world.

The primitive world of our ancestors was filled with dangers and its workings would have seemed confusing.  Cooperating with nature by knowing how certain things worked would have seemed vital to our survival.  For instance, understanding why the Sun moved and how and why the seasons changed would have been important; understanding the weather would have been important; understanding why people got sick and diseased would have been important; understanding what caused the plants to grow and the animals to move would have been important, but how do you explain all of that?  Before the laws of motion and gravity were established; before plate tectonics and atmospheric and oceanic physics were explained; before microscopic germs, viruses, and bacteria were discovered; before the laws of thermodynamics, the process of photosynthesis and metabolic pathways were described; people had no clue as to the correct answers.  But people still needed answers to complete their sense of cause and effect so they could begin to understand how the world worked in an attempt to cooperate with it.Ancient Religion1

To take one example: noticing that the seasons change is important because when that happens we notice that some animals migrate at certain times of the year, plants grow and die at certain times of the year, and the temperature changes at certain times of the year.  When we draw connections between one thing and a second thing in the world – such as animals migrating when winter comes – we are creating relationships that complete our sense of cause and effect.  We can now better predict the effects of our actions on the world.  With human intellect, however, humans differ from other animals in that we not only notice that the seasons change, we can ask *why* the season changes.  Due to the relationship nature of causes and effects, it’s possible that knowing more about the first thing might help us understand more about the second thing.  So understanding why the seasons change might keep us from staving or freezing by helping us to better predict when the seasons will change.  People all over the world noticed these things and tried to answer the questions the best they could and they did it in the same basic manner – by invoking gods and spirits as causes to these unexplainable actions and events.  Thus in a prescientific world, the invention of religion with an accompanying set of beliefs about how the world works helped to complete a cause and effect understanding of the world for early human societies. Next, we’ll incorporate the role of the supernatural and spirituality into the origin of religion.


Further reading:  The Dominate Animal by Paul and Anne Ehrlich; The Demon-Haunted World by Carl Sagan; The Magic of Reality by Richard Dawkins; Breaking the Spell by Daniel Dennett

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Capitalism’s Problem: Exponential Growth in a Finite System

The global economy has expanded at an ever increasing rate during the past century, increasing at a rate of exponential growth.  A study done by a Professor of Economics at the University of California at Berkley estimated world GDP increased to $41.016 trillion in 2000 from $1.102 trillion in 1900 – a growth rate of approximately 3.617% per year.  While GDP only implies the market value of all good produced, all aspects affecting the economy have been increasing at an exponential rate, from human population growth to agricultural production, to industrial production, consumption of raw materials, and pollution.  Nearly all economists and most people view this feat as a positive achievement and they look to continue this same pattern of growth into the foreseeable future.  Hardly any are asking if this pattern is sustainable.

First, a word on exponential growth.  Exponential growth is a quantity which increases proportionally to what is already there.  This is different from linear growth, where a quantity increases at a constant rate over a given period of time.  Consider folding a piece of paper measuring .025 cm in thickness.  You have just doubled the thickness of the original piece of paper.  Fold it again and you have quadrupled the original thickness.  Fold it a third time and this piece of paper is 8 times as thick as the original paper, measuring .2 cm.  Continue folding until you have done this 30 times and how thick do you think the paper is?  The paper is now 268.44 km.  How about another ten folds to 40?  This paper is now 274,877 km long, over halfway from the earth to the moon.  And with one more fold the thickness will pass the moon.  Nine more folds, totaling 50 folds from the original thickness and our paper is now 281,474,976 km, well past the distance from the earth to the sun.

For any quantity to grow exponentially it does not need to double every period, and you can easily calculate an approximate doubling time for a given growth rate.  If the original sheet of paper only ExponentialvsLinearShortExponentialvsLinearLong increased it thickness by 10% every “fold” (or period increase) the approximate doubling time would be 7 folds.  This means it will take approximately seven times longer for the thickness to reach the sun, or about 350 folding periods.  This is the power of exponential growth. In the short run exponential growth is not much different from linear growth.  The impact lies in its long term effects.  Now, given that our businesses want to expand their output exponentially, does anybody see a potential problem here?

The obvious problem is that we live on a planet with finite space and resources.  Consider world metal production which has risen at a rate of 5% historically.  In 2008 more than 1.8 billion tons of metal was produced.  If this pace were to continue in a little over 700 years the yearly mining output would be greater than the entire mass of the planet.  However we would actually mine the weight of the planet in a single year much sooner than this because this figure only refers to the amount of metal produced, not the tonnage of ore needed to be mined to produce the metal, which is much greater.   Obviously this can’t happen and just as obvious, this is a problem for our current economic system.  As I see it, the question that we need to be asking in our economic and policy debates is what happens when our economic system, which depends on exponential growth, reaches the limits to growth?  The only possible answer is that it breaks down.


Further reading: Limits to Growth: The 30-Year Update by Donella Meadows; Collapse by Jared Diamond; One With Nineveh by Paul and Anne Ehrlich

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Evolution Unshrouded Part 5: Why Evolution Matters

“Nothing in biology makes sense except in the light of evolution” – Theodosius Dobzhansky, 1973.

Biology, the science of life, has an enormity of subfields – marine biology, biochemistry, botany, genetics, microbiology, ecology, which interact with many other fields – medicine, agriculture, economics, environmental science, climate that influence our everyday lives.  Understanding evolution is therefore critical in making informed decisions about various topics, problems, and issues.  Let’s take a look at some.

Medicine – Since bacteria and virus have such short generation times, they evolve very quickly.  Understanding this salient fact yields some useful knowledge such as:

  • Flu vaccinations should be taken yearly as viral strands rapidly evolve
  • Antibiotics shouldn’t be overused (or taken for viruses for that matter) as it will encourage the evolution of resistant strands
  • If antibiotics are proving unhelpful in fighting a bacterial infection you may be up against a resistant strand.  Taking a stronger dose will only increase the selection pressure.  Instead, take a combination of different antibiotics.
  • Understanding genetics allows people to manage hereditary diseases

Agriculture – Billions of dollars are lost every year as a result of ignoring evolutionary theory.

  • Monoculture can lead to a lack of genetic variation, making them vulnerable to disaster due to changing environmental conditions
  • Using a preventive spraying of pesticides leads to pests evolving resistances to those pesticides and rendering them less useful in the future.  Pesticides should only be used as necessary.

Economics – Misunderstanding evolutionary theory results in economic losses in many industries.  A new field called Evolutionary Economics is growing up around the idea of combining evolutionary theory with economics.

Environmental Science – We are rapidly learning about the ecosystem services that maintaining a healthy environment provides humanity

  • Hunting and farming for the largest animals, or animal traits, puts a strong selection pressure on being smaller.  As elephant poachers hunted for elephants with the largest tusks, those with smaller tusks had a reproductive advantage resulting in small tusks spreading through the population.  Fishing for the biggest fishes results in selection pressures for smaller fishes.  Hunting and farming should strive for proportional size yields.
  • Understanding the evolutionary history of organisms can help preserve biodiversity that allows ecosystem services such as: clean drinking water, decomposition of waste, nutrient dispersal and recycling, providing energy, food, and raw materials, and so on

Climate – Climate provides a strong selection pressure on nearly all life on Earth

  • Plants sprout, flower, and grow earlier in the season if the climate is cooling and later in the season if the climate is warming.  This affects planting and harvesting of many crops.

This is not by any means a comprehensive list although it should be easy to see that understanding and applying evolutionary theory has a wide range of effects on humanity.


Further reading: Guns, Germs, and Steel by Jared Diamond; Collapse by Jared Diamond; The Revenge of Gaia by James Lovelock; One With Niniveh by Paul and Anne Ehrlich; Betrayal of Science and Reason by Paul and Anne Ehrlich

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Evolution Unshrouded Part 4: The Evidence for Evolution

The evidence for evolution is abundant in size and vast in scope, consisting of lines of inquiry from multiple fields converging on this single great insight.  With that said, the rich evidence available in the fossil record would be sufficient to prove that the evolution of species has occurred.  Although the fossil evidence alone would fill many volumes, I will attempt to summarize and outlineHuman Fossils the main lines of evidence here.  As good as any place to begin, I suppose, is the fossil record.

  1. The Fossil Record – Sometimes when a plant or animal dies its hardened remains can be preserved or fossilized through a variety of physical and chemical processes. These hardened remains reveal the physical history of our ancestors and show clear linkages and intermediaries between past and present groups of species.  Intermediaries between all kinds of groups of animals have been found such as between fishes and amphibians, reptiles and mammals, dinosaurs and birds, terrestrial mammals and whales, human and chimpanzee, and so on.  Many intermediaries were predicted *before* the actual fossils were found, showing the predictive power of evolution.
  2. Artificial Selection – Charles Darwin began On the Origin of Species with a section on
    Evolution of Corn

    Evolution of Corn

    artificial selection, which is similar to natural selection except that it is humans rather than nature  selecting for particular traits.  Auroch’s, the ancestors of some of our domesticated cattle, have been modified by repeatedly selecting for qualities such as their ability to produce milk, aggressive behavior, and so on.  Corn was breed for size and calorie content and barely resembles its ancestor strains.  Artificial selection is evident in the domestication of other plants such as wheat, rice, and various fruits and vegetables, and animals such as dogs, cats, sheep, goats and racehorses.

  3. Microevolution observed in the laboratory – Microevolution has been observed many times in the lab.  A famous example is from the lab of Richard Lenski, an evolutionary biologist working at Michigan State University, that has been running a long term E. Coli evolution experiment since 1988 with a duration of longer than 60,000 generations that has shown evolution in action.  The evolved resistance of DDT in fruit fly’s is another example.
  4. Evolution observed in nature – Evolution is sometimes difficult to notice occurring in nature due to its slow, gradual process that requires a lengthy timespan of many generations.  This is why its easier to observe in the lab by using bacteria or fruit fly’s which have shPeppered Mothsorter time spans compared to many other plants and animals, such as humans, red wood trees, and foxes.  In any case, evolution has still been observed a few times nature.  The classic textbook example is that of the peppered moth changing its color due to selection pressures from pollution during the Industrial Revolution in England.  Other observations include: populations of flowers blooming earlier due to warming weather; insects evolving resistances to pesticides; and lactose tolerance (technically called lactase persistence), and the sickle-cell trait (a perfect example of natural selection given that the geographical distribution of the gene for hemoglobin S and the distribution of malaria in Africa virtually overlap).  This leads us to…
  5. Geographic distribution of plants and animals – The observed snapshot of the characteristics of plants and animals fits what would be predicted by modern evolutionary theory.  Populations of closely related species should resemble those in close proximity to each other Geographic Distribution of Animalsand gradually become less similar as you move further away.  While on his historic voyage aboard the HMS Beagle, Charles Darwin noticed that finches and tortoises on the Galapagos Islands resembled those on the South American mainland and concluded that “one species had been taken and modified for different ends.”  This phenomenon is observed all of the world and is explained by the geographic speciation of plants and animals.
  6. Evidence from DNA – A process known as DNA sequencing, which determines the order of the nucleotides in a DNA molecule, can be used to compare the DNA of any two species.  Modern evolutionary theory predicts that closely related species – those with a recent common ancestor such as humans and chimpanzee – should share a higher percentage of their DNA than more distantly related species – such as humans and frogs, or humans and pine trees – and guess what?  They do.
  7. Vestiges in species –  A vestige in biology is a part or organ of an organism that has become reduced or functionless in the course of evolution.  The examples in nature of abundant.  Whales have no hind legs but have tiny bones in them which are remnants of the hind legs of their walking ancestors from the distant past.  Birds such as ostriches do not fly but have stubs of wings from their flying ancestors.  Numerous species who now live in the dark have lost their eyes but still contain eye sockets.  All mammals, including humans and the other tailless primates, have a tail at one point in their development.  Humans have a tail for a period of about four weeks in our embryological development and we possess a tailbone when born, despite not having a tail.  Along with a vestigial tail humans have a long list of vestiges.  We still possess the genetic machinery to make our hairs raise when we’re cold (to trap in more heat) or when we’re afraid (to appear larger) even though we have lost most of our hair.  We call this goosebumps.

This list barely scratches the surface of the evidence for evolution but provides a good place to start.  The evidence for evolution is extremely vast and conclusively proves evolution as a fact.  Knowing that evolution is a fact, we can now look at why understanding evolution is important.


Further reading: The Greatest Show on Earth by Richard Dawkins; Climbing Mount Probable by Richard Dawkins; The Blind Watchmaker by Richard Dawkins; Human Natures by Paul Ehrlich

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