Edge of our Solar System

Voyager I has traveled 11 billion miles toward the edge of our solar system and has not reached the boundary yet.  Maybe it will be difficult to define where this point is located.  Scientists have been looking for a clear break between our solar system and interstellar space, but there may not be something that obviously separates the two.

Certainly, Voyager has detected a substantial increase in the level of galactic cosmic rays, which could be evidence that the spacecraft has crossed through a small zone called the heliopause, into a new zone where plasma bubbles have been blown outward by the solar wind.  Think of the tear-drop bubbles blown by children which are captured and then transported by the wind.  This might be a good analogy as to what our solar system looks like, but it does not explain the mystery of its edge.

A year ago, Voyager passed the termination shock, where the solar wind of charged particles abruptly slowed down, indicating Voyager’s entry into an outer region called the heliosheath.  Then last August, the Voyager entered an unknown “magnetic highway” where magnetic fields inside and outside the heliosphere connect.

However, even though Voyager has penetrated into the Kuiper Belt, it has not reached the Oort Cloud, which might require another 11 billion miles.  And who knows what lies ahead for our steadfast traveler.  Quite frankly, Homo sapiens may not be around by the time Voyager reaches what could have been considered by our species as the end of our solar system.

One may speculate that the matrix of the universe is such that dark energy and dark matter form the skeletal structure with our solar system connecting to other solar systems like cells in our body, forming galaxies.  Then the galaxies will merge into other galaxies so that the entire universe is interconnected.  If that is the case, the edge of our solar system and galaxy will have no more meaning than the boundary where one cell in a biological organism touches the next.

Then is there an edge to our universe?  There should be if there are no other universes.  The edge of the entity that surrounds us, which we call the universe, began with the Big Bang.  The universe, which had boundaries early in its existence, still must have these borders.  Scientists claim that this universe is expanding, but there can be no increase in diameter unless there is an edge for the diameter.  In other words, how can the universe expand unless it has a boundary creating that entity which is increasing in size?  If our universe had no edges, then it would be headed toward infinity, not expanding in a finite system.

But it seems quite useless to argue that our universe has no edge since we are aware of something we call the “universe” that contains all the galaxies.  And we can mathematically show the amount of mass within this closed universe.  And we can show the percentages of dark energy, dark matter, and visible matter within our universe.

We may not know much about our solar system, much less our galaxy, even to a lesser extent our universe, but we do know we are part of its contents and we have edges.  At least we appear to be confined within one skin and not floating about.  Do you believe that gives us an edge when we speculate that the universe has a boundary?

How Much Do We Know?

With all the improvements in science and scientific research and space exploration, how much do we know… perhaps 10% of what is in our universe?  With the large telescopes on earth and in space, how much do we see… perhaps another 10% of our universe?

Actually, we know less than 1% of what is in our universe and probably much less than 1%.  The visible universe is less than 4% of what is included in the universe and probably much less than 4%, especially if the universe is an ellipse and we can only view it to its horizon.  And even if the visible universe is 4%, we know just a fraction of what is in that visible universe.

So, how much do we know?  Not much at all.  We don’t know much about dark matter and don’t know anything about dark energy.  In fact, we can say with certainty:  we are pretty much in the dark.

We don’t even know that much about what is right in front of us.  The invisible quantum world is right next to us, but we have only scratched its surface.  There are unexplored deep oceans.  There still are many mysteries deep inside the earth’s core.

We, humans, think very highly of ourselves, but actually we are a miserable lot.  We can’t take care of our environment.  We are responsible for a current mass extinction that may end up being worse than the Permian extinction.  Our emotions make us more violent and unpredictable than any other animals.

We don’t even know much about ourselves and why we exist.  Why do we think about our existence?  If we didn’t have that nagging awareness, we could be like all the other animals, living through basic instincts without emotional interplay.  But our consciousness and consciences make us different from other animals… and not necessarily different better.  We murder based on hate, greed, sex, desire, jealousy, and anger.  No other animals do that.  We want gold, silver, diamonds, and currency.  Other animals don’t care about these things.  We want luxury automobiles and huge homes with the best furniture.  Other animals could care less.

So, why are we different and what is our purpose?  Well, logically there must be a reason for us to have free will and make choices based on our unique consciousness and consciences.  And the only reason that makes sense is that we are being tested.  Why else would we be able to make choices?  Life with free will would be quite absurd without consequences for our choices.  Existentialism rules our world.

Homo sapiens could have been like any other animal with no awareness or conscience, but we were given free will that no other animals have.  Why?  It has to be because something or somebody will examine these decisions that we have made.  And, of course, there will be consequences.  You cannot judge an animal that acts based on inherent instincts, but you can provide punishment for bad choices made by Homo sapiens.

So, how much do we know about a future judgment?  My guess is that we know less than 1% and probably substantially less than 1%.

Focus on God

Our species appears to be the only animal that thinks about the afterlife.  The majority of humans think that there is an afterlife or there is not an afterlife or they simply don’t know one way or the other.  But most of us do think about the afterlife.

And we think about the Creator or God in the same manner:  there is a God or there is no God or we just don’t know.  But most of us do think about God.  Our focus is on God.

Even atheists need God to believe that He does not exist.  So logically, they must have thought of God first in order to decide that He does not exist.  Because how could you introduce a negative thought about something that you didn’t think or know about?  The concept of God had to exist before atheists could argue that He did not live.

Thus, our focus is on God and the afterlife.  And since we are human, we will do stupid and cruel and mean and horrible things during our lifetimes.  Everybody has something they can feel guilty about and most of us have something we feel guilty about every day.  So, we are sinful creatures who have been given free will to commit sins.

Do we resign ourselves to this sinful nature or do we try to do better?  Those who give in to our humanness and never attempt to improve themselves typically are those who don’t believe in God.  And who could blame them?  If you accept sin as your natural state during life, then you would not want any consequences after death.  You would not want God to be your judge.  Your preference would be to die and that would be the end.  The only problem with this belief is that choices without consequences make no sense.  Life would be absurd without consequences.  Life would be absurd without God.

Yet, those who believe in God are not necessarily any better than atheists.  Many followers of God believe that they will have a free ticket punched, eliminating all consequences for their sins.  This makes no more sense than atheism.  Clearly, the Bible speaks of judgments and consequences based on what we did during our lives.  Of course, believers want their sins to be washed away, typically so they can go sin again.  The only problem with this belief is that there must be consequences or life would be absurd.

And those who do not know if God exists or not cannot win by default.  You have heard the rule of law: ignorance of the law is no excuse.  The same applies to those who say they don’t know if God lives.  When they sin, there will be consequences whether they know God or not.  There must be consequences to prevent life from being absurd.

In conclusion, atheists, believers, and agnostics, who represent the majority of Homo sapiens, all focus on God in one fashion or another.  And that focus is on there being or not being a judge who will provide consequences for all our poor choices made during our lifetimes.  But remember: life is absurd without consequences.

Evolution for Afterlife

We are all familiar with Darwin’s theories of evolution during life, but very little has been written on evolution after life.  If you believe that there is nothing after life, then you will not be interested in this discussion; however, you might want to read this just in case there is something waiting for us after we die.  Since it is impossible to say with certainty that there is nothing after we die, it might be good to at least think about the possibilities.

You have heard stories about parents who wanted their children to have a better life and sacrificed their own lives to provide an education and whatever else they could to give their children a better chance than they had.  Evolution is a part of that process.  Survival of the fittest is one of the evolutionary principles that generally create a better and stronger species.  The weaker and less efficient members of that population die or don’t reproduce.

We know that Homo sapiens was lucky to become the dominant species.  If the dinosaurs had not suffered a mass extinction, mammals would not have had the opportunity to flourish.  And our species was nearly wiped out several times, but it fortunately survived the eruption of Mt. Toba and the ice ages.

So even though we consider ourselves as the ultimate species at the top of the evolutionary peak, this is not true.  Consider the source of that belief.  Our species consists of very fragile animals that cannot survive in extreme conditions.  The species has only existed for a short period in geologic time.  Our selfish tendencies will eventually doom us.  We would rather satisfy our individual needs than do the right thing to protect our progeny.  An example is our inability to preserve our environment for future generations.

We attempt to improve ourselves during our lifetimes, but our humanness limits our ability to evolve into selfless creatures.  Perhaps the best we can hope for is that we would sacrifice our lives to protect our children.  So, it may be that any significant evolution of man must occur after death.  Assuming that we are still conscious after death, we may have the opportunity to evolve into a much better entity.

The Bible indicates that there are three Heavens (2 Corinthians 12:2).  We can only speculate on these different Heavens, but there may be three separate tests for each Heaven.

The first Heaven probably is the obvious one where Christians go if they believe in Jesus who died for their sins.  But Jews and Muslims also know this Heaven as a place where believers of God are admitted.  Other religions and beliefs are not excluded from this Heaven.  This destination is not an exclusive club for Christians, Jews, Muslims, or any religion.  But your choices made during life may be a part of the judgment, including analyzing your actions as evidence that you actually believed.  So, this Heaven perhaps is the easiest to reach as long as you believe.  There may be a clear division between believers and nonbelievers.  The Bible refers to an abyss between the two groups.  Near-death experiences consistently refer to crossing over.

We apparently will retain at least some of our senses to detect this Heaven.  This is the Heaven that has been seen and heard by those who have had near-death or death experiences.  It probably is a beautiful and peaceful place, but still should be within the confines of God’s created, closed universe.  This is where we may see and talk to relatives and friends who predeceased us, angels, and Jesus and Abraham, all in recognizable human form.  This probably is by design so we will feel welcome and will not be afraid of unfamiliar forms and entities.  The face of Jesus will be comfortable and familiar to us, so we may see Him here.  But the face of God might be more hidden from us in this Heaven.

The second Heaven may require an evolution of spirit, going from selfish, centrist thought to “big picture” thinking.  In other words, you become less important as an entity as the whole becomes more important than your part.  This Heaven, more than likely, is reached through your thoughts.  You may find the mid-Heaven quite a bit more difficult to reach since there may be temptations in the first Heaven that impede your progress.  However, if you become one with God, you should be able to avoid selfish and prideful thoughts.  Some religions teach this unification, which is critical in order to evolve and transfer into the second Heaven.  Reaching this goal requires much more than a belief in Jesus or God; it requires a complete makeover of your personality, focusing on the universe that is beyond you.  I have no idea about the structure of this Heaven, but it probably is still within the border of our closed universe.  We may be judged by our actions in the first Heaven to determine if we will be permitted to transition to the second Heaven.

The third Heaven probably is God’s universe, which is outside our known universe.  The law of conservation of energy basically states that matter and energy can neither be created nor destroyed in a closed universe.  So, God’s creation probably occurred outside our closed universe in God’s kingdom.  The transformation that is required to reach this kingdom may be of such a magnitude that I would be surprised if many souls ever made it.  In fact, the Bible, including the teachings of Jesus, is very clear that only a very few make the grade to reach God’s kingdom.

Pastors rarely will discuss the three Heavens and even less often will mention the difficulty in reaching the third Heaven, God’s kingdom.  It would be too controversial.  The pastors would be run out of town.  Most believers only want to hear about the first Heaven, which is the easiest destination.  So, ministers focus on how members of their church can reach the first Heaven.  It would be difficult to sell Christianity or any other religion if people had to work too hard at it.  So, don’t expect too many articles on evolving from the first Heaven to the second and third Heavens.

The significant evolution of our spirits must occur after we die.  My wife and I look forward to the Heavens as a challenge.  We will do our best and reach as many Heavens as we can.  We believe we have a chance to reach the second Heaven, so we will prepare ourselves as much as we can during our lifetimes to be ready for whatever happens.

If there is no afterlife, then all will be still when we die, and we will not suffer from our beliefs.  However, if there is an afterlife, then we will be well served by our preparation for consequences.  The free will that God gave us must have some significance.  As religious existentialists we believe that free will without the consequences of God would be quite absurd.

Also, it seems logical that a creation must have a Creator and that a design must have a Designer.  If I were an odds maker, I would say that it is more likely than not that there is a God.  If I were a gambler, I would place my money on God not only because of better odds, but also because of the consequences if you are wrong.  Even if the chances of there being a God were one in a million, I would still bet on God because if I’m wrong, it will not cost me anything.  But if I don’t pick God and I’m wrong, it will cost me everything.

My wife and I have taken a vow of abstinence for the past twenty years.  We will die without having sex again.  This may seem a bit extreme, but believe me, getting to the other Heavens requires extreme effort.  It will not be easy, no matter what religion and beliefs you have.  You must be willing to sacrifice yourself and your desires.  My wife and I study the Bible together as we prepare for our final days.  We are not perfect, but we work toward reaching the final goal.  If you get halfway toward your goal each day, you will never reach the goal, but you will keep edging closer.

It is interesting that many people do not like their lives, their work, their sex lives, their sex (male or female), but there are days when my wife and I find that we don’t like our species.  We apologize for this, but sometimes, we like our dogs better than humans.  In fact, we hope God has animals in the first Heaven.  We feel confident that the second and third Heavens require a complete transfiguration from our species into something altogether different and, of course, becoming a better entity through the evolution for afterlife.  Good luck.  We all will need it.

I Wish I Were an Atheist

I truly wish I were an atheist.  If I were an atheist, I would not have to worry about consequences… at least during my lifetime.  If there were no God, then this would be the best thing for mankind for there would be no consequences for all our poor choices.  Even the best of us make poor choices, so every human should hope that there is no God to judge us.

Of all the possible scenarios for afterlife, the best for mankind is for us to die and that is it.  After death, everything is black and nothing happens beyond that point.  Then nobody has to worry about being punished for bad acts and stupid decisions.  Death and then no more is the best case for Homo sapiens.

However, this is not very probable.  Everything within our universe is cycled and recycled.  The famous first law of thermodynamics is that matter and energy are neither created nor destroyed.  In other words, in our closed universe, our body, mind, and spirit are all recycled after death.  In other words, we may still be aware of where we are after death.  That, in and of itself, presents some problems for us.

If we are still thinking after death, what will we be thinking?  If we are not distracted by the daily chores of life, we will probably be thinking about bad decisions that we made during life.  It is natural for us to be hard on ourselves if our senses are not leading us in another direction.  Our senses, as we used them during our lifetimes, may not even be functioning after death.  Our consciousness or awareness may be our primary sense at this stage.

If we have free will during our lifetimes, God cannot intervene.  He gave us a moral compass or a conscience to guide us as we make decisions.  We can’t blame God for our poor choices or for the misfortunes we encounter on earth.  God is the creator, who lives outside our closed universe within which nothing can be created nor destroyed.

If there are no consequences for our choices made during life, then life is absurd.  If I die and there is nothing else, then our conscience and consciousness are absurd.  If there is no creator, then a closed universe sitting in the middle of nothing and surrounded by an imaginary boundary is absurd.  (Caveat:  a creator can be any power outside our universe that created our universe.)

So, the best case for humans during life is to be atheists and believe there is no God.  The only problem is that if you are wrong, then the afterlife will be a nightmare.  Thus, if you are an atheist, you must believe completely and absolutely that there is no God and there is no afterlife.  You must bet everything you own, including your soul, on there being nothing after death.

However, it is more likely than not that there is something after death, simply because of the commonality of cycles within our universe.  So, it probably would be better to suffer the pain of thinking about consequences, so that we will be better prepared to deal with judgment day.  If you believe that there is a God who forgives you, then the afterlife may be more tolerable.

Stromatolites – Our Ancient Ancestors

Our earliest ancestor was a plant, not an animal.  This most ancient ancestor was a stromatolite dating back more than 3.5 billion years ago or about a billion years after our earth was first formed.   Stromatolites consist of blue-green algae that aggregates, creating layers.  Even though most of our early ancestors have gone extinct, stromatolites still exist today.  A large population is located in the Hamelin Pool in Shark Bay in western Australia.

Stromatolites were the most abundant fossils found in rocks dating to the Precambrian era, from the origin of Earth about 4.5 billion years ago to 544 million years ago.  Stromatolites became prolific starting about 2.5 billion years ago, releasing oxygen into the environment which set the stage for animal life.  Both plant and animal kingdoms diversified over the years, but stromatolites remained the same since they were able to adapt to many environments and did not require diversification to survive.  They formerly existed all over the world, but today they are endangered.

Over billions of years, both plants and animals evolved into large trees and dinosaurs, but there were many mass extinctions that cut off the branches in our family tree.  One of the most widely discussed was the death of the dinosaurs, which occurred about 65 million years ago.  The K-T boundary or thin geologic line representing the end of the Cretaceous and beginning of the Tertiary ages included iridium.  Iridium is found primarily in meteors.  This was strong evidence of when the large mountain of a meteor about six miles wide crashed into the Yucatan Penninsula near the town of Chicxulub in Mexico.

Scientists are fairly confident that this meteor caused significant stress on the dinosaur population, but are not certain if this event could have accounted for the mass extinction by itself.  However, if you examine the effects of the meteor’s impact, it might be sufficient.  The impact set off volcanic eruptions, massive earthquakes, and tsunamis, all sending dust and debris into the atmosphere, where it blocked sunlight for centuries.  This created a nuclear winter with temperatures plummeting.  There were wildfires all over earth, causing acid rain.  This sounds pretty convincing, but there is one more piece to this puzzle.

About this same time, a large volcanic eruption occurred in the Deccan Traps located in the northwestern part of the Deccan Plateau in India.  It may be the largest volcanic province in the world, consisting of more than a 6,600-foot depth of basalt lava flows covering an area of 190,000 square miles.  When the event occurred, some estimates show that 580,000 square miles were impacted.  This would have been a significant event, which when combined with the meteor could have been too much for the dinosaurs.

Some scientists believe that the Deccan Traps eruption occurred first about 66 million years ago, lasting for thousands of years, and then the Yucatan meteor smashed into the earth about 65 million years ago, causing a double whammy which wiped out the dinosaurs.  However, it may be more than a coincidence that the Yucatan impact area is on the opposite side of the world from the Deccan Traps.  If you place your finger of your right hand on the area where the meteor landed and a finger of your left hand on the Deccan Traps on a globe of the earth, these locations are eerily opposed to each other.

I don’t believe in coincidences.  I would argue that the time lines need to be reexamined.  It is more likely that the meteor stuck first, which triggered the great Deccan Flats eruption.  Whether this occurred 66 or 65 million years ago is not known, but it must have been closer in time than scientists believe.

Mammals were able to survive these events and over time, an animal called Homo erectus popped up in the east African rift zone about 2 million years ago.  These hominids were able to stand upright, so we believe that we descended directly from them.  Homo sapiens seem to have entered the scene about 500 thousand years ago, and the subspecies Homo sapiens sapiens, which is very similar to modern man, can be found about 200 thousand years ago.

Our subspecies just barely hung on after the mega-volcanic eruption at Lake Toba in Indonesia about 75,000 years ago.  This was the biggest eruption that we know about during the history of earth, which caused a nuclear winter just like the Yucatan meteor and Deccan Flats eruption.  Our species came very close to being wiped out.  There were only about a thousand of our species that survived this event, which explains why all humans are so genetically similar.  After surviving the ice age, our species started repopulating the earth about 10,000 years ago.

So the bottom line is that Homo sapiens sapiens has not been king of the earth for very long.  In the great scheme of things, we should examine all our ancestors and realize that we are very insignificant in the great scheme of things, not only in the amount of time that we have occupied the earth, but also in our vulnerability to changes.  We have been very fortunate that we are right in the middle of a warm, moderate period, but will we survive the next ice age or cataclysm?  Time is really not on our side.

Instinct vs. Choices

Homo sapiens have been provided some instincts such as self preservation and species preservation, but we seem to be different than all the other animals on this planet in that we also make choices, unrelated to obtaining food, shelter, or sex.  As an example, we may make decisions based on whether we consider the act as being right or wrong.  This seems to separate us from the others in our animal kingdom.

This gift of a decision-making process does not come without consequences, though.  Even if you do not believe in consequences in an afterlife, there are consequences within our lives.  If you choose the door with the tiger behind it, you will, more than likely, be eaten.

Biological psychologists wrestle with some very difficult questions.  (1) Can our minds work independently of our brains?  (2) Why do humans have an ethical basis for their decisions?  (3) How does heredity influence behavior?  We will discuss these questions later to see how they impact our choices.

But let’s start with instinct.  Instinct is a label for a category of behaviors that are found in different species.  When we say that female elephants take care of their babies based on a maternal instinct, this is only a label that does not explain how the behavior developed in elephants.  But these labels are important and seem fairly consistent throughout the animal kingdom.  Many species have a maternal instinct, which helps preserve the species.  Some biological psychologists avoid the term instinct as being offensive to their studies, but it is very beneficial when talking in general terms.

There is a strong maternal instinct in our species.  Our brains are hard-wired to protect our young since this allowed humans to survive predators in the wild.  Many mammals have young that are not strong enough to run away from a hungry predator, so an instinct to preserve our species is deep within us.  Humans don’t wonder whether there will be consequences to us.  We react instinctively when we protect our young.

Now, let’s examine choices.  When our species makes a decision, is it because biological factors forced a behavior or did they enable the behavior to occur?  For example, there are areas of your brain that increase the likelihood of you being pushed into aggressive behavior.  But you will make choices on your response to that force.  Your past experiences, the current social setting, the legal consequences, and current motivations will all come into play when you make a decision.  When murderers were asked if they chose to commit the murders, they answered in the affirmative.  You make choices every day and there are always consequences, which temper your decisions.

So, let’s examine the first question above:  can our minds work independently of our brains?  There are two theories:  (1) the dualists believe that our brains interact with our minds, while (2) the monists believe that the brain is a machine and consciousness is irrelevant to its functioning.  Most religions follow dualism since when our brains die, we arguably continue thinking with our minds.  And our ethical and moral values play a significant role in making choices.  Descartes, a French philosopher, was a dualist who believed that there was something other than the brain that recognized that “I think, therefore I am.”

If you believe that we respond like machines, then we really don’t have any choices.  We are predestined to do everything that we do.  We would be hard wired to make decisions.  If this were true, wouldn’t we all be making the same basic decisions?  For example if we found a lost wallet with $100,000 inside it, would everybody make the same decision on what to do with the money?  You would have some people who would return the wallet and money and others who would return only the wallet and pretend that they found it without the cash inside.  The final choice will be based on many complex factors and should not be a typical mechanical decision.

This is a transition to the second question: why do humans have an ethical basis for their decisions?  Is there a part of our brain that has a conscience?  There may be parts of the brain that may be stimulated to provide relief from pain or depression.  But it is not known if the brain can be manipulated to provide a conscious in the decision-making process.  In other words, can a portion of the brain be stimulated to make a person make better choices based on something other than personal gains?

The answer why our species seems to be unique when it struggles with ethical decisions is based on many factors.  Certainly, how we are perceived by others, our religious beliefs, and how penal systems will respond to our actions may forge a conscious.  Man struggles mightily with ethics, so there must be some reason that is lodged somewhere in our thoughts, different than in our brains.

Then the final question is: how does heredity influence behavior?  An ontogenetic explanation of our behavior starts with our genes and traces how the genes combine with the influence of the environment and our experiences to produce the final outcome.  The genes that were more successful were passed on to future generations as the genetic makeup that had weaknesses were phased out over the years.  For example Homo sapiens probably had a conservative gene that made our species more cautious and patient in our responses.  Those of our early species who were too impatient were eaten by predators, so natural selection preserved those genetic propensities to take our time and think things through before jumping into harm’s way.

As we discussed, birds do not need to be taught how to build nests since that behavior is largely instinctual.  However, humans need to be taught nearly everything we do.  We have a survival instinct for ourselves and our species, but we make most of our decisions with our minds in gear, not our brains.  We make many conscious choices every day based on our individual moral fiber.  So it may come as a shock to many people that genetic differences are also an important determinant of variation in a wide range of human behaviors.  A growing list of behaviors— including major measurable aspects of personality, political conservatism, religiosity, occupational attitudes, social attitudes, marital status, and even television watching—have all been shown to be inherited traits.

In conclusion, our decisions frame who we are and who we want to be during our lives.  But our decisions also play a significant role in the afterlife.  In other words if you are still thinking when you die, then your brain will decompose leaving your mind to continue into the afterlife.  The choices that you made during your lifetime will follow your thoughts after death.

Has Man Been Around for Millions of Years?

How long has man been around on our planet?  Well, it depends on your definition of man.  If by   man, you mean Homo sapiens, then the answer is no.  We have only been on earth for about 200,000 years.  But if you mean man to include our ancestor, Homo erectus, the answer is yes.  We have been around about two million years.

The ultimate common ancestor of all modern people was an early Homo erectus in Africa who lived at least 1.8 million years ago.   Early African Homo erectus fossils, dating back to about 1.8 million years ago, are the oldest known early humans to have possessed modern human-like body proportions.  These features are considered adaptations to the loss of earlier tree-climbing adaptations, including the ability to walk and possibly run long distances.

The most complete fossil individual of this species is known as the ‘Turkana Boy’ – a well-preserved skeleton, dating around 1.6 million years old.  Microscopic study of the teeth indicates that he grew up at a growth rate similar to that of a great ape.  The Turkana Boy does not look much like modern man.  Actually, he looks more apelike.  But there is fossil evidence that this species cared for old and weak individuals.  The appearance of Homo erectus in the fossil record is also often associated with the earliest axes, the first major innovation in stone tool technology.

The earliest skeletal evidence of modern man, Homo sapiens, also came from Africa.  These finds were about 200,000 years old.  They then appear in Southwest Asia around 100,000 years ago and elsewhere in the Old World by 60,000-40,000 years ago.  This evidence seems to support the argument that Homo sapiens came out of Africa, sometimes referred to as the “replacement model.”

The alternative model was called “regional continuity,” which theorized that Homo sapiens originated regionally rather than out of Africa.  The DNA data seems to support the regional theory.

Geneticists at Oxford University found that the human betaglobin gene is widely distributed in Asia but not in Africa.  Since this gene is thought to have originated more than 200,000 years ago, it undercuts the claim that an African population of modern Homo sapiens replaced East Asian archaic humans less than 60,000 years ago.

It is apparent that both the complete replacement and the regional continuity models have difficulty accounting for all of the fossil and genetic data, so it might be best to take a middle position, the assimilation theory.  It takes a middle ground and incorporates both of the models.

Gunter Brauer, of the University of Hamburg in Germany, proposed that the first modern humans did, in fact, evolve in Africa, but when they migrated into other regions they did not simply replace existing human populations.  Rather instead, they interbred to a limited degree with late archaic humans resulting in hybrid populations.  In Europe, for instance, the first modern humans appear in the archaeological record rather suddenly around 45,000 years ago.  The abruptness of the appearance of these Cro-Magnon people could be explained by their migrating into the region from Africa via an eastern Mediterranean coastal route.

They apparently shared Europe with Neanderthals for another 12,000 years or more.  During this long time period, it is argued that interbreeding occurred and that the partially hybridized predominantly Cro-Magnon population ultimately became modern Europeans.  In 2003, a discovery was made in a Romanian cave named Peştera cu Oase that supports this hypothesis.  It was a partial skeleton of a 15-16 year old male Homo sapiens who lived about 30,000 years ago or a bit earlier.  He had a mix of old and new anatomical features.  The skull had characteristics of both modern and archaic humans.  This could be explained as the result of interbreeding with Neanderthals according to Erik Trinkaus of Washington University in St. Louis. 

Alan Templeton, also of Washington University, reported that a computer-based analysis of 10 different human DNA sequences indicated that there has been interbreeding between people living in Asia, Europe, and Africa for at least 600,000 years.  This is consistent with the hypothesis that humans expanded again and again out of Africa and that these emigrants interbred with existing populations in Asia and Europe.  It is also possible that migrations were not only in one direction–people could have migrated into Africa as well.  If interbreeding occurred, it may have been a rare event.  This is supported by the fact that most skeletons of Neanderthals and Cro-Magnon people do not show hybrid characteristics.