Human Evolution; Out of Africa; and the Impact of Dogs

[wellwisher]

I never said these were domesticated dogs. This is what you and others have assumed and said.. Domestic dogs works under the assumption that the ape-man was in charge of the pair. I said the dogs and ape-men were both wild/natural but formed a symbiotic connection this may be harder to see, since sucker fish may not always be found near dead sharks.

Dogs were only domesticated about 10,000 years ago, but their evolutionary history goes back way further than that--as witness one of the earliest canines yet discovered, Hesperocyon, which lived in North America a whopping 40 million years ago, during the late Eocene epoch.

All indications are that the genus homo has been consuming meat for > 2,000,000 years.

This may be true, but meat is not their primary diet. Meat is the primary diet of dogs. The ratio would go up.

One point I made that, I will ask of the existing theory, is how do territorial animals learn to deal with having to invade territories during migration? This is important since there is a huge difference between being stationary and defending a territory, being and mobile among defensive stationary animals that hunt day and sometimes night.

 

[origin]

Dogs were only domesticated about 10,000 years ago, but their evolutionary history goes back way further than that--as witness one of the earliest canines yet discovered, Hesperocyon, which lived in North America a whopping 40 million years ago, during the late Eocene epochs

Really? Yes some sort of mammal that had dentation that could be called canine existed about 40 million years ago, but the most closely related canine to the dog is the grey wolf which has only been around for about 1 million years.

When presented with lots of data that is counter to your idea it may be a good thing to stick to your guns if you are a lawyer or a talking head on Fox 'News', but it is pretty much fatal in science or in my field of engineering. You of course can believe whatever you want but I have always felt it is best to let the data lead to the conclusion and not pick only the data that supports a preconcieved idea.

 

[Randwolf]

When presented with lots of data that is counter to your idea it may be a good thing to stick to your guns if you are a lawyer or a talking head on Fox 'News', but it is pretty much fatal in science or in my field of engineering

Oh, stop origin. It's wellwisher, this is his modus operandi, do not strip it from him. After all, what do you expect? All of a sudden wellwisher makes sense? Please... See Einstein's definition of insanity...

 

[origin]

Oh, stop origin. It's wellwisher, this is his modus operandi, do not strip it from him. After all, what do you expect? All of a sudden wellwisher makes sense? Please... See Einstein's definition of insanity...

Point taken, but I think it is always a good idea to include some real information in a thread, that way someone who is unfamiliar with the evolution of man won't get the wrong idea that wellwisher's ideas other than his idle musing and it may spark a reader to research this fascinating subject.

 

[wellwisher]

For my information, how does the current theory and the data explain how a territorial animal (defensive), survive when it migrates and becomes the constant intruder in the territory of other defensive animals and predators, most of which it has no clue of? How does a day animal survive in territories with nocturnal predators, if they have no history of this situation?

Evolution and natural selection helps to tune to the conditions in which it evolved. To be optimize in the original place, may not be all that is needed for migration to new places. This needs migratory skills or as an ally.

A small animal might dig a hole as a protective defense.This strategy works as long as food is close by the hole, for retreat from predators. If he has to travel further and further to find food, this method of defense becomes ineffective, unless he can build another hole down the trail.

A migratory predator can live off the land and will not show defensive stepping. He is designed to invade and sniff out prey. I would assume the early ape-man had a good defense strategy, based on knowledge of their original local situation. Did they recreate such defenses, and then move these as they moved since their evolution was selected by this? Is this seen in the data? Or did they act like migratory predators without a clear evidence of a defense trail?

If they allied with dogs, of sorts, there should be no defensive stepping evidence.

A study in the current issue of PLoS Genetics (2014) suggests that, instead, dogs and gray wolves share a common ancestor in an extinct wolf lineage that lived thousands of years ago.

An international team of researchers generated genome sequences from three gray wolves – one each from China, Croatia, and Israel, the three countries where dogs are believed to have originated. They then sequenced the genome of a basenji dog from central Africa and a dingo from Australia. Both the regions have been historically isolated from wolf populations, according to a press release by The University of Chicago Medical Center. Analysis of these genomes from the wolves and the dogs showed that the dogs were more closely related to each other than they were to the wolves. The wolves, too, were closely related to each other than to the dogs.

Additionally, the scientists did not see a clear evidence linking dogs to any of the living wolves that were sampled.

Below is a relative of the dog from 20 million years ago called the hesperocyon

 

[origin]

For my information, how does the current theory and the data explain how a territorial animal (defensive), survive when it migrates and becomes the constant intruder in the territory of other defensive animals and predators, most of which it has no clue of? How does a day animal survive in territories with nocturnal predators, if they have no history of this situation?

Evolution and natural selection helps to tune to the conditions in which it evolved. To be optimize in the original place, may not be all that is needed for migration to new places. This needs migratory skills or as an ally.

A small animal might dig a hole as a protective defense.This strategy works as long as food is close by the hole, for retreat from predators. If he has to travel further and further to find food, this method of defense becomes ineffective, unless he can build another hole down the trail.

A migratory predator can live off the land and will not show defensive stepping. He is designed to invade and sniff out prey. I would assume the early ape-man had a good defense strategy, based on knowledge of their original local situation. Did they recreate such defenses, and then move these as they moved since their evolution was selected by this? Is this seen in the data? Or did they act like migratory predators without a clear evidence of a defense trail?

If they allied with dogs, of sorts, there should be no defensive stepping evidence.

No other animals need to be taught how to live and function in their environment including the other primates, why do you think that we did? It doesn't really make any sense.

A study in the current issue of PLoS Genetics (2014) suggests that, instead, dogs and gray wolves share a common ancestor in an extinct wolf lineage that lived thousands of years ago.

This is a possible alternative to wolves being a direct ancestor, but currently the dog (Canis lupus familiarisis) is thought to be a subspecies of the gray wolf. Regardless, this has no bearing on your ideas.

 

[wellwisher]

No other animals need to be taught how to live and function in their environment including the other primates, why do you think that we did? It doesn't really make any sense.

Let me rephrase the question. The great apes are not migratory animals by nature. If you went into an area that contains great apes and displaced them and forced them to march outward outside their normal territory, will this create a problem for them?

Many species go extinct when humans develop the land and displace the local animals who are not adapted for such major change. The reason is they evolved within a certain set of environmental parameters, and are not suited for large parameter swings. If we took animals from the Galapagos and brought them to the Grand Canyon, the parameters will change so most will also go extinct.

To migrate through, and then out of Africa, the pre-humans had to constantly change environment, climate, terrain, flora and fauna while entering hostile territories guard by other animals trying to survive. The question I have is how did a normally stationary animal, adapted to a specific place, cope with constant changes of parameters and hazards?

My contention is this would create extreme hardship with high levels of attrition for great apes. They would stop short unless they could either acquire the skills needed, or team up with animals more suited to the migration. They could follow these animals.

I was asking how does the consensus theory explain this, since this cuts the heart of all scenarios.

In parts of Africa (Serengeti ) many animals will migrate together during the dry season looking for water. There is a truce. Only the crocodiles remain true to form picking off the animals as they try to drink. But lions will drink near their prey during the truce. I content humans and dogs formed a truce allowing the humans to learn survival skills.

There were not millions of pre-humans migrating together, so trial and error could work. Small groups would need to acquire skills quickly and constantly. Picture 20 members of Sciforums hiking from South Africa to Libya without supplies or any books. They would all die. This might be possible for highly skilled people who know how to live off the land, anywhere. But not people used to being in one place with all needs met.

 

[Arne Saknussemm]

I think you know, but are not really considering that when any animal migrates, be it a gorilla or a man or whatever habitually territorial animal it would be because conditions are poor and getting poorer in his territory. No man, and very certainly no gorilla and his family are just going to take off into the unknown at a fancy. Conditions probably forced them to look elsewhere for food and water, and as you guessed, the adjacent territory may be no better or occupied by hostiles of whatever species - their own or another. So they keep moving. I am sure you understand me, but for example when our human ancestors crossed the land-bridge from Asia to North America, it wasn't a matter of some man or woman saying, "Alrighty then, today we go to America! And we'd better hurry because that land-bridge may disconnect without a moment's notice." It must have been generations of families and clans slowly moving westward, and occasionally even eastward again before they were truly in North America proper. They probably never even were aware they were living on a land-bridge or considered which continent they were on.

 

[Arne Saknussemm]

Picture 20 members of Sciforums hiking from South Africa to Libya without supplies or any books. They would all die. This might be possible for highly skilled people who know how to live off the land, anywhere. But not people used to being in one place with all needs met.

A pretty picture indeed! But I don't think so. As much as I share your enthusiasm in imagining SciForum members lost and starving in Africa, I think they're more clever than that. First of all, why books? I would hope they have enough knowledge in common sense in their hard hard heads to see them through. See, sometimes my daughter insists on watching reality shows like Naked and Afraid even though she also finds them laughable. The contestants are supposed to be things like ex-Navy Seals who grew up as feral children on the streets of Nome, Alaska and have taught survival for good money for many years. How can this be? I ask because the tough guy is soon drinking water out of a hole he hand-scooped in the jungle floor, and wondering why he got diarrhea and whining about it!. The woman won't eat creepy-crawlies and loses thirty pounds in twelve days. So just who are these highly skilled people you mention? Me, I'm a city kid through and through. I love to visit out of the way places -in the car! Appreciate the beauty, take a few pics and haul my fat butt back to town for a cappuccino because I noticed hot coffee was conspicuously absent in the midst of Shenandoah National Forest. Nevertheless, common sense and hunger would tell me that if I had to spend two weeks in the jungle and make it to a pick up point, I wouldn't waste any time making a knife, twining vines into rope and building a bamboo hut. I might contrive some sandals and a sunshade, and I would make clean water my priority. I would eat absolutely anything that was safe (because they're going to give me a million dollars if I succeed), and I would slowly pick my way to the pick up point from day one. I would not linger and waste time setting up camps until I was at the pick up point. Then I would conserve my energy as much as possible, keeping away dangerous animals by building a fire, which even I know how to do. So if I know this much, I think our friends at SciForum could do even better. They'd figure it out. Some of them are pretty smart cookies. However, I hope you realize they would need years and years to walk from South Africa to Libya. It's about 8,000 kilometers.

 

[origin]

I think I see your problem. You are looking at this like a group of people packed there bags and took off on a migration.

First lets look at our closest relative the chimpanzee. They live in small groups and in the savannah environment they have an home range on the order of 120 to 560 sq km.

Based on that I think it is a fair assumption that early man had about this size of a home range. As a population grows the range will grow and because of the pressure of finding food. In times of plenty there would be no problems but in times of drought the pressure would be such that it is quite easy to imagine the group splitting and moving to opposite ends of the territory. The 2 groups would then expand their territories from those new centers. Lets further assume that the splitting of the group occurs on average about every 5 generations. Currently humans have a 'new' generation about every 30 years - I think it is safe to say that in the bad old days of 200,000 years ago a generous generation time would be 20 years. So these occurences would not even be thought of as any sort of migration to the people at the time due to the very slow expansion relative to the generation length and the life span of the humans.

So based on this how fast would a migration take?

So the average size of the territory is about 340 square km. Assuming a roughly round territory that means every 100 years the 'migration' would have moved about 10.5 km. So in 1000 years the migrations would have been 105 km. After 10,000 years the migration would have been 1050 km and after 100,000 years the migrations would have been 10,500 km. That is the sort of distances that could have been traveled without any one individual every consisdering themselves to be migrating.

In the past 50,000 years are so there have developed true nomadic people that had very sophisticated weapons and tools and followed migrating animals. The migration rate of these people would MUCH higher than 10.5 km every year.

So in short there is no need for your concept of dogs teaching people how to migrate - because it was more of a drift that they did not even realize was happening.

And by the way our nearst relatives wage war to expand their territories and they weren't helped out by dogs.

Chimp war.

I don't recall you ever changing your mind so I do not think you will now but at least there is some other information on the thread besides the 'idea you came up with several years ago'. So, I think I am done on this thread. Enjoy.

 

[Arne Saknussemm]

So that 'Ape will never kill ape.' stuff we see in the old Planet of the Apes movies is all wrong?

 

[origin]

So that 'Ape will never kill ape.' stuff we see in the old Planet of the Apes movies is all wrong?

Hey you're right! Geeze, now I am questioning the whole premise of those fine theatrical presentations...