Talk:Timeline of evolution/Archive 1

100ka Skin Color

"100ka: Mutation causes skin color changes in order to absorb optimal UV light for different geographical latitudes. Modern "race" formation begins."

Is there any study or evidence for this? As opposed to skin, hair, and other changes coming about from interbreeding with the other lines of hominid who were already in Europe and Asia? If so, a reference would be good.

Since humans originated in Africa, doesn't this indicate that humans originally had dark skin and that light skin was an adaptation to permit greater production of vitamin D?

Lungs from swimbladders?

I thought the general consensus was that swim bladders evolved from lungs, or at least that a generic swim-bladder-lung is ancestral to both?

See e.g. Wikipedia swim bladder article and [http://www.britannica.com/eb/article?eu=120748 "Fish." Encyclopædia Britannica. 2004. Encyclopædia Britannica Premium Service. 27 Aug. 2004]

kYA instead of TYA ?

I'd like to change the notation slightly to be more in line with SI standards. In particular, I'd like to use kYA instead of TYA.

Are there any objections?

Works for me, do it! -Vsmith 16:41, 22 Nov 2004 (UTC)

Magic

There's this statement: Neanderthal man (Homo neanderthalensis) makes magic, bury the dead and care for the sick.

Burying the dead is deducible from finding graves, care for the sick is deducible from the bones of injured individuals who couldn't have survived unaided. But where does the statement they practiced magic come from? (There's nothing about this on the Neanderthal page) I suppose burial itself might be considered a magical act, but that's not what we today generally call magic.

Burial in modern times are associated with religion and rituals. The magic here probably refers to such rituals and a belief in after-life, precursors to modern religion.

Also, in one neander grave they found remnants of a hat and a rabbit skeleton. (j/k)

60 kYA ?

What about the events 60kYA and 150kYA ? Is it a joke or something ?

Not jokes, but actual scientific results obtained by comparing the genetic material of a wide selection of modern humans. The numbers come from biological measures of inbreeding.

Since female humans have no Y chromosome (except in a few rare instances which I'll ignore), Y's are only inherited from men, and there's no (or very little?) mixing of genetic material. If you have a Y, you got it from your dad. The only way to change the Y is to have a mutation. Since mutations occur at a known, (approximately) constant rate counting up the number of mutations necessary to cover all modern variants of the Y chromosome gives the amount of time which has passed since the life of the last male ancestor of all living human males. See [1] and Y-chromosomal Adam.

You can do something similar to calculate the age of the last female ancestor of all living humans. The mitochondria in your cells has a different set of genetic material from the cells / cell nuclei themselves. Your mitochondria come only from your mother since a sperm carries its mitochondria at the base of its tail - which is shed at fertilization. The zygote thus retains mitochondria only from the ovum. Analyze a large sample of mitochondria extracted from the cells of many different people of different ethnic groups to get an estimate of the number of mutations that have occurred and you can calculate the age of everyone's great-great-great-...-great-grandmother. See [2] and Mitochondrial Eve.

Scientists have named the two individuals described above as Adam & Eve, although there were older humans and the two people didn't coexist. Incidentally, you could probably do something similar to determine the age of the last common ancestor of humans & chimpanzees, humans & new world monkeys, humans & dogs, etc. You'd run into trouble at some point, though, since the mechanisms of reproduction vary somewhat between species and I'm not sure how much you have to assume about the age at which reproduction happens. SMesser 17:54, 7 Jan 2005 (UTC)

Y-chromosomal Adam was not "the last male ancestor of all humans alive today." He was the last male-line-only ancestor of all humans alive today. They are two different concepts.

For example, the last male ancestor of me and my cousin Aaron is our maternal grandfather. (His mother is my mother's sister). But I am not closely related to his father, nor he to mine, so our last male-line-only (Y-chromosomal) ancestor, tracing back through our fathers and our father's fathers etc., lived much further back in time. --Cam 15:36, Apr 16, 2005 (UTC)

self-reproducing RNA molecules?

Is there an evidence for that? I mean, do we have the kind of evidence on this as we have on -for example- the first lifeforms found on earth? If there is, it's not mentioned in the RNA world hypothesis article, which I find very strange. If wikipedia does indeed maintain a NPOV, this should really not be in the article. It does, however say that this theory -at least in it's present state- is very improbable.

The evidence is admittedly scant. But then, the first lifeforms on earth to leave fossils were fairly complex. Bacteria, viruses, prions are all fairly simple critters, but don't generally leave fossils the way things with hard shells / bones do. The first lifeforms were probably even smaller and simpler. Talk.Origins[3] has a nice, detailed discussion of the stages between no life and life as we know it, as well as a set of technical links to many of the stages, including the RNA world hypothesis. That Wikipedia article also has several external links supporting the hypothesis.

In the interest of brevity, I'd rather not have external links at every stage of the Timeline of evolution page. For this entry, I think links to RNA world hypothesis and Origin of life are sufficient. Since it is a hypothesis (rather than a leading theory) with only scant evidence, I think the word "possibly" is essential. I've also deleted the word "first" since the boundary between auto-catalyzing (or mutually-catalyzing) chemical reactions and actual life is vague, and the RNA world might have been one of the later stages of abiogenesis.

If you'd rather replace the RNA world entry on Timeline of Evolution with something else, I'll be satisfied as long as the new entry reflects an intermediate stage of abiogenesis the mainstream science community considers somewhat plausible.SMesser 17:41, 24 Mar 2005 (UTC)

My only concern is -even though the article does say "probably"- that the scientific community only accepts abiogenesis as a basis for a lack of better explanation. Now, I might sound like a creationist nut for saying this, but I don't think we should accept this as a valid standpoint. If we do, however, we should provide links to all theories about the origins of life (even non-scientific ones, since at this stage, science simply cannot provide a good answer to that question), or -preferably- none at all. My point is, that right now this is a matter of belief (in the non-religious meaning of the word).

I'm really hoping that this suggestion won't start a creationist-abiogenesist flamewar.

AndrasGerlits 11:06, 26 Mar 2005 (UTC)

First things first - you can use a sequence of four tildes (~) to sign your posts. Added benefits include a nifty timestamp and a link to your talk page (where you can get & respond to messages that might not be interesting to the broader community). It also helps readability when multiple people are discussing something.

Second, evolution is a scientific term and theory, so Timeline of evolution should emphasize the scientific standpoint. As a scientist (Ph.D. in plasma physics), I am personally biased in favor of giving the scientific POV as much screen space as possible. I'll try not to let that get in the way of writing NPOV articles.

There are several points of view which may not be scientific, but which are completely valid from a religious / philosophical point of view. I'd put creationism & intelligent design in that category. Science is as much a philosophy and a problem-solving / technology-building tool as anything else. Maintaining NPOV probably means we should make at least passing reference to those on anything as contentious as the origin of life.

Getting back to the specific topic, I'd rather not list all the different ideas floating around about how life got here. Crossing the "genes-first" and "metabolism-first" models with the four location models (ocean, clay surfaces, deep subterranean, and extraterrestial), we get eightvery broad scientific hypotheses, each with its own proponents, weaknesses, sub-categories, etc. We shouldn't spend the time to outline each of them here. That's what the link to origin of life is for. The various creationist models show a similar variety in the level of divine intervention, the age of the universe, and the way in which creation happened. Creation vs. evolution debate outlines a number of additional ideas which don't fit neatly into either of the above categories.

I'm horrible at brevity.

I'd also argue that the scientific community has more to support their ideas of abiogenesis than a lack of a better explanation.

Anyway, what do you think of the following entry:

4000 MYA | Life appears, probably in some form much simpler than any modern cell. See origin of life. The atmosphere doesn't contain any free oxygen

If absolutely necessary, we could put some link to creation vs. evolution debate at the top, although I think the contextual link to evolution and the links on origin of life are sufficient. Timeline of evolution isn't a stand-alone page, so we don't need to link in as much stuff directly.SMesser 22:46, 25 Mar 2005 (UTC)

I'm very much impressed by your constructive approach to my suggestion. Yes, I do think that the sentence you're proposing is a step in the right direction, and would be glad to see those changes. However, I think you're confusing science with materialism, a misconcept shared by many. I still believe that the scientific approach (which is the only true NPOV) would be not to mention even abiogenesis (note, I'm not saying we should give any explanation to the origins of life on earth), since that's a materialist dogma (since it's a philosophy, not a methodology) and not a scientific fact. AndrasGerlits 11:06, 26 Mar 2005 (UTC)

What's wrong with the use of materialism in science? I thought this is the ONLY way to do science?

Science does not equal materialism. Science is a methodology designed to use our senses when analysing our environment, any scientific theory must adhere to the scientific_methods, some of which abiogenetic theories clearly do not. For example, they cannot be falsified. Materialism on the other hand, is a philosophy, a certain belief in the way the universe works, when certain thing are assumed without needing any proof. Nothing is taken for granted in the natural sciences. AndrasGerlits 11:52, 30 Mar 2005 (UTC)

Then what is material science?

You're joking with me, right? Also, what's that new stuff about the self-replicating molecules? This section is getting worse by the minute. We should just get rid of the whole thing. AndrasGerlits 08:57, 2 Apr 2005 (UTC)

I'm sorry, but I was under the impression that self catalytic RNA wasn't exactly controversial, rather *some* people dispute whether this was enough to qualify as biological reproduction, you can after all test for catalytic activity without too much effort--Bah' 00:22, 7 October 2005 (UTC)

You're wrong. I gather you're one of the wishful thinkers on this matter, so I'd like to draw your attention to one of the very fine books by Hubert P. Yockey covering this very issue. It might be very mathematical, but than again, we're talking about mathematical models.

This section should be removed altogether. Talking about self-reproducing RNA in this context is just lazy.

An RNA World where certain RNA sequences tend to be more common than others in an "RNA soup" is fine. Where they start evolving, spewing out lipids and DNA, and spawning Life As We Know It, is (bad) science fiction. Its inclusion here undermines the credibility of an otherwise fine article. Why not change it to something like the following?

Self-organizing RNA molecules may have existed, providing potential building-blocks for the subsequent emergence of life.

And I see no reason why a scientific article needs any links to creationism pages. However, please consider that secular theories without a firm basis in evidence are just as out-of-place in a scientific article as purely religious treatments of the matter. 68.81.105.126 02:07, 23 September 2006 (UTC)

Tunguska event

I added the Tunguska event just to remind our human readers that collision with Near Earth Objects have always been happening. I have not even included the near-misses discovered in recent years. Flattening 2000 square km of forests to me is quite a significant change to earth and might have caused certain species(though not human) to be extinct. It all depends on your perpectives. It seems that smaller collisions are more frequent than bigger ones , which really change the course of evolution. We ourselves have a real possibility of following the footsteps of the dinosaurs. Such catastrophe really put man's ego in their humble and correct place.

Tunguska event removed from timeline

I removed the Tunguska event from the timeline, because it has absolutely nothing to do with the evolution of life on Earth, nor did it have any significant effect on the Earth itself. 157.181.71.7 06:07, 19 Apr 2005 (UTC)

Evolution is at best a Theory

It's nice to think about how and why we exist on this planet but at best, these thoughts that we as individuals have, can only be answered with a philosophical answer. Let's face it, we all live with a philosophy of life. Some have bought into this notion that in the THEORY of Evolution, life sprang forth from non-living material, which was given the exact conditions it needed for this to occur.

Before you even begin to entertain this idea, I would ask you to think about this one thing. Where did the information come form in order to have life in any form, exist under any condition?

I would suggest that evolution and the theories thereof, is more closely related to a religion by which great faith must be exercised in order to explain that which is not subject to real science scrutiny of the ideas and theories that are not able to be observed and or duplicated in a laboratory.

So before any further meaningful discussion about evolution can be explored, lets have a moment to examine our motives for wanting to adhere to this theory and in that, present it as such....just another theory to try and bring meaning to our lives. For if all it does is to explanation our being, then what real purpose does it serve in our fragile humanity.

Regards, B.E.

Some have bought into this notion that in the THEORY of Evolution, life sprang forth from non-living material -- it would help if you would actually read the article on which you are commenting, not to mention the millions of words that have been written on science, evolution, information theory, and the various other topics on which you have expounded completely erroneously and fallaciously. -- Jibal 13:56, 11 May 2006 (UTC)

Sigh...click here for a definition of theory in the scientific sense. As Isaac Asimov said, "Creationists make it sound as though a 'theory' is something you dreamt up after being drunk all night." And no, evolution is not a religion. Can you name anyone who thinks evolution "brings meaning to their life"? Look, it's perfectly okay to be religious - but what are you trying to accomplish by making everyone who doesn't agree with your personal beliefs religious? If you want to reject the 150 years of scientific support for evolution, and believe in the literal interpretation of your religion's sacred text, that's fine. Just admit that you do this on faith rather than reason, and that this has no place in a science classroom. Isn't religion supposed to be based on faith, anyway? - 68.33.120.32 00:34, 27 November 2005 (UTC)

What do you mean? You seem to be self-contradicting. You begin by saying that the question of life should best be answered by philosophy and yet when you examine evolutionary theory you advocate the use of labaratory work. What are you trying to say?

Who knows? Who can fathom the psychology of the Creationist? Maybe he's having a crisis of faith. - 68.33.120.32 01:06, 27 November 2005 (UTC)

Qoute, B.E. :"theories that are not able to be observed and or duplicated in a laboratory". Observance of evolution, that is; DNA sequencing and comparing, is one of the most common way of typing and identifying bacteria and other organisms. The small changes in DNA sequences are observed, even between a few generations. If you refute this, you are at best oblivious. Induction of mutations (I.e UV-radiation) has been used since the 1930s to create bacteria with special features. Making mice glow in the dark is another example of how to create "evolution" in a laboratory, though this might not apply to you as more than support for your "Intelligent design". In fact, you are right, Intelligent design has happend, though not before the 20th. Sentury.

.......

Evolution is a theory with powerful evidence behind it, evidence that does not depend upon cultural biases. It explains phenomena lacking any other credible explanation. Darwinian evolution proves consistent with later discoveries in genetics, biochemistry, astronomy, paleontology, archeology, and of course comparative anatomy. Does anyone question the obvious similarities between humans and chimpanzees in physiology? We don't have to see something happening to know that somethig has happened. Just as linguists have been able to demonstrate that languages as diverse in time and distance as Icelandic and Sanskrit derive from the same early speech that has left no recorded evidence, biological evidence leaves overwhelming evidence of processes of agonizing sloth that have allowed evolution of life. Just as one has no need for direct evidence in written records that classical Latin evolved into modern French, Italian, Spanish, Portuguese, and Romanian when nobody was paying attention, one does not have to see evolution at work to know that it has happened.

The evolution-creation debate largely hinges not so much religion versus amoral godlessness as it does upon the interpretation of one specific tradition of religious reality versus everything else. It is possible for some evolutionists to accept the necessity of a supernatural power in establishing the ultimate laws of reality in physics, mathematics, and logical structure and exercising the daring choice of letting things go as they did. Some reality exists that no intelligent life can ever know (think of the uncertainty principle) and one can define such unknowable truth as the realm of a supernatural entity.

Creationism is scientifically indefensible. The Biblical chronology makes no sense unless someone wishes to accept that God created a universe about 6000 years ago that appears to be older by a magnitude of over one million -- a view that establishes God as a devious forger of evidence that contradicts His Plan. If one wants to make sense out of the veritable divinity of ethical standards that determine how a few tribes of shepherds and farmers could adapt to early civilization could maintain some cohesion even as the world changed around them, then so be it. Nobody can prove with science alone that human life is precious, that the application of force or fraud to take what someone else worked for or received as charity is wrong, that integrity in ordinary trade and in testimony before judgments is necessary, and that reckless sexuality that leaves children confused about their place in society is unconscionable.

Evolution cannot tell people moral right from wrong any more than can mathematics. But it is useful in explaining things and improving life. We can test medicines and treatments upon animals that have certain similarities to us. Many human medicines are first tested in veterinary medicine which would be inapplicable to us if we were so different from dogs that we had nothing in common with them. Dogs aren't particularly close relatives to us among the mammals.

Evolution is at best a theory -- but so is creationism. Evolution is more reliable and has more utility. If it can't tell us right from wrong, then neither does mathematics or physics, neither of which is rejected. If we want to study right and wrong, then we might as well study religion and jurisprudence such are to be found in the Torah and English common law, or at least the philosophical specialty of ethics. A Creationist framework is never going to offer us a cure for cancer other than prayer; an evolutionary framework might allow medicine to find a flu-like virus that selectively kills cancer cells. A virus that kills cancer cells but leaves the rest of us alone will give people far more cause to praise God than will some proof that the Earth is 6000 years old.--Paul from Michigan 15:43, 12 March 2007 (UTC)

Lemurs and Fossas

In the timeline Lemurs seem to have moved from Africa into Madagascar 64MYA and 40someting MYA. Was it a long crossing or did they do it twice, or is one crossing to be removed?

The fossa (Cryptoprocta feroxis), a close cousin of the mongoose and a member of the viverrid family, is the largest carnivore on the island of Madagascar. The viverrid family is an ancient line of carnivores that are thought to pre-date wolves, cats, hyenas, and other lineages of meat-eaters — none of which are natives of Madagascar (http://news.nationalgeographic.com/news/2004/06/0602_040602_fossa.html). Granted that Madagascar does have a very unique and unusual collection of 200,000 or more plants and animals, including "35 species of lemur found nowhere else on Earth," and yes, the ancestral fossa and other early carnivores and primates may have "drifted ashore on rafts of vegetation" 21 million years ago; however, I do not think that these events are worldy enough in significant to be on a timeline of evolution on Earth. These are cases of allopatric adaptive radiation on one island. We have no mention of Darwin's finches here? The reference to the migration of early carnivores to Madagascar is a refernce to evolution that took place on one island. It fails to cite a reference, and for the above stated reasons, I am removing it. Perhaps Wiki should have a separate article on the Evolution of Carnivores on Madagascar. Valich 17:33, 12 February 2007 (UTC)

Anthropoids

An anon just added this:

Anthropoids : Bugtipithecus inexpectans, Phileosimias kamali and Phileosimias brahuiorum similar to today's lemurs , lived in rainforests on Bugti Hills of central Pakistan

"Bugtipithecus inexpectans" and "Phileosimias brahuiorum" each only get one google hit, to the same page from a non-English website, [4]. "Phileosimias kamali" gets me no hits at all. Can anyone confirm this info. func(talk) 06:42, 1 Jun 2005 (UTC)

1. Ice Age/isthmus 2. Homo chokepoint

1) Neither here, nor Wiki entries on the ice age I found, discuss the idea that the raising of the Isthmus of Panama [mentioned here] is the ultimate beginning of the global thermohaline circulation, which in turn led to the ice ages. Many think adaptation to the resultant chaotic climate is what drove human evolution over that tiime period. Worth a mention?

2) Toba volcanic eruption at 74 KYA. I've seen the human "chokepoint" population mentioned in several places at circa 10,000, nothing close to 2,000. Consider using a range.

It's great to see all this timeline in one digestable piece!

Skookum172.193.251.124 17:55, 3 Jun 2005 (UTC)

Eukaryotes

Isn't the emergence of eucaryotes as early as 2100 MYA debated? --EnSamulili 06:21, 28 July 2005 (UTC)

Also, isn't the claim that the origin of life at 4 billion years still being debated? Scanning through some recent news articles, I get the impression that there isn't direct evidence of life past 2.8 billion years. I think it'd be more accurate to put a range of years for this or some other indication of the uncertainty. -- KarlHallowell 20:03, 5 September 2006 (UTC)

The earliest evidence for life that scientists agree on is stromatolites found in Australia which were made by blue-green algae (also called cyanobacteria) 3.5 billion years ago. There is some earlier evidence from Greenland based on carbon isotope ratios, but it is controversial.

Human brains are modern by 40KYA

From achaeological and cultural remains, we know that the human brain has evolved to its modern cognitive powers by 40KYA. Some recent achaeological studies have pushed that to an even earlier date. (evidence in Zaire etc) Hence 40KYA is also refered to as the Great Leap Forward by Jared Diamond in his book "Guns, Germs and Steel". This intelligent humans rise up to the top of the food chain and become the masters in the animal kingdom. Hence it follows that the reason why Africans do poorly while Eurasians did so well has nothing to do with IQ (they all have the same IQ ) but rather to do with geography. At 10KYA, those people that happen to live near fertile places with many animals for domestication get to start farming and agriculture, which beings about societal differentiation, sohistication and size. However , anatomically , humans have reached the modern state by 200KYA from studies of OMO1, OMO2 and Herto in Ethiopia. As to why this Great Leap Forward happen is still a mystery. One recently proposed theory is that the Toba volanic eruption at 70KYA has selected only those more intelligent humans who are able to survive the calamity.

Old World Primates in Africa before Collision with Asia?

"New World Monkeys have prehensile tails and migrate to South America. Catarrhines stay in Africa as the two continents drifted apart." This is a very confusing statement for 30MYA. Don't the primates evolve in Laurasia 55MYA. Old World group moves into Africa 20MYA after Africa collides with Asia. There should only be lemur-type prosimians in Africa 30MYA. New World monkeys move into South America from North America 5MYA when those two continents are joined. The classic Old-New World primate split occurred in Laurasia not Gondwana.

Please note my comments about primate contradictions on talk:timeline of human evolution. - UtherSRG (talk) 19:54, 25 October 2005 (UTC)

Human history

While this is rightly a broadly geologic outline rather than an anthropological one, I wanted to suggest three things to slightly fill out the last six or seven points .

• Moving the beginning of recorded history back 1200 years to keep it in-line with the invention of writing in Sumeria (3200 B.C.).
• Mention the industrial revolution, one of the "big two" revolutions alongside agricultural.
• Mention nuclear weapons and the possibility of our destroying all higher lifeforms. Sensible? Marskell 15:41, 13 October 2005 (UTC)

Good suggestion. Why don't you add it in yourself? I don't think you need any permission, as long as you put down your justification. As long as there is no contradiction with the rest of the timeline, it should be ok.

.......

I have chosen to add four technologies because of their significance in changing human behavior. All have discrete times in which they came into existence and clear moments of introduction.

The printing press reshaped the way in which people store and disseminate information. Cheap books and pamphlets allowed political changes to spread rapidly; cheap maps made travel for any purpose far easier. Inexpensive printing allowed knowledge to be stored long beyond the time of the discoverer and in far more places. People no longer had to travel far to read a specific book; they could have a book travel to them. The difference between the failure of Jan Huss to challenge corruption within the Catholic Church and the success of Martin Luther was that Huss had to rely upon word-of-mouth and that Luther could rely upon printed documents reaching multitudes. Besides, printing became the basis of some of the first true capitalist enterprises not tied closely to land ownership and agricultural production.

Three others (telephone, recorded sound, and electric light) came into existence at roughly the same time and changed how people communicated, stored data, and lived. Like the printing press, they had clear moments of introduction, and even if they are supplanted by such other innovations as computers, laser disks, and LEDs, they shaped the way people did things with such later innovations. The telephone is the first medium of instant messaging accessible to non-experts. Recorded sound (also relevant to data storage and retrieval)allowed non-musicians to have first-rate music in their homes (that is, I don't need to have two violinists, a violist, and a cello player nearby to listen to a Mozart string quartet, and I can listen to Glenn Miller's Big Band performances long after his death). Incandescent lights blurred some of the ancient distinction between day and night for multitudes and even allowed people to travel, transact business, study, and perform surgery at night. These date from a period of fewer than five years and stimulated a modern capitalism that depended upon the workers as a market. It may be my opinion, but the changes that these inventions wrought upon the way in which people live are likely to outlast the effects of the automobile, an innovation that I cannot so clearly associate with a specific time.

I consider these three inventions more significant than the automobile because even if fuels disappear and people must return to wind-powered, steam-powered, horse-drawn, or pedal-powered travel, they might still have portable computers with LED monitors that would be impossible without electric lights and data storage, and unlinkable without some successor of the telephone (or radio). That people read from computers recognizes a pattern that began when Gutenberg printed the Bible. The desire for information and entertainment seem even more powerful than Wanderlust.

Reaping machines certainly allowed human populations to explode -- not that overpopulation is progress, so those are good candidates for inclusion. As for the atom bomb -- to date, more people have been killed in warfare through incendiaries, ammunition, and conventional explosives delivered by aircraft to a war zone that extends far beyond the frontline of battle. I could also add radio, which set the pattern for satellite communications. But fuel consumption that makes motor vehicles expensive to operate will likely make air travel a rarity as well should the motor fuels get scarce.

What the heck? I will add wireless telegraphy (obvious predecessor of radio and television, let alone satellite broadcasting) and the aircraft, two inventions that have remade the world. Like the telephone, recorded music, and electric light I can bunch those two in a short time. --Paul from Michigan 17:39, 12 March 2007 (UTC)

Extinctions

Might I suggest Timeline of exctinctions? If we start adding them here, there will be no end to it. Extinction events, OK. Marskell 11:25, 25 October 2005 (UTC)

I think extinction is central to the theme of evolution of life , where the tree of life is being pruned and re-trimmed. Without extinction, there would be not much evolution! On the other hand, I do not know what is the use of putting the nuclear bomb( which just killed a tiny fraction of people compared to guns) in. Do you want to put that in the timeline of weapons invention? This is about evolution of life in its grandest scale on earth, not human technology. Most experts say we are in the midst of another mass extinction. In conclusion, I do not understand why people here just removed things without discussing it first. There is really no basic courtesy. Since this is an encyclopedia , I will rather err on the side of more than enough and abundant info as long as it is true than the lack of it due to the censorship of some bias person, who is just one minute little fraction of this global population. As a wikipedian, I am disappointed. It takes a lot of effort to add new information, but just a few keystrokes to remove it.

The information is still there in the history and can be redacted elsewhere. My thought is the "if this then why not that" problem. I realize there are some important prehistoric extinctions listed here but if we go for extinctions in the modern era how do we decide how many is too many and which should be included? The bomb makes sense because it can destroy all higher life on the planet. — Some bias person, er, Marskell 10:02, 27 October 2005 (UTC)

In thinking this through some more, what do people think of the following:

• Moving all key human landmarks from 10kya onward to Timeline of human evolution and leaving (or adding where missing) broad ecosphere, evolutionary changes. Obviously humans would still get mentioned but it would re-focus things. For instance, remove climbing Everest but add cloning the first animal.
• Start the Timeline of extinctions and move what I removed there. Marskell 13:19, 27 October 2005 (UTC)

I noticed an inconsistency regarding the number of major extinctions. The first extinction flags itself as the first of seven. I could find only six listed. On the Timeline of Extinction, five is said to be the agreed upon number of major extinctions. 67.86.40.120 16:53, 15 December 2005 (UTC)Brett D.

Homo-Sapiens and Homo-Floresiensis

Forgive, what you may call, my ignorance. I am a Catholic mother who is trying find information which is not only palatable to my admittedly creationist sensibilities, but that will also provide my children with an intelligent and sensible source of education regarding the history of the world from it's creation.

Since scientific theory and religious theory are NOT mutually exclusive, and, since modern science has repeatedly confirmed biblical historical points rather than refuting them, I feel no reason not to teach evolution to my children as a theory.

However; when I reach 27 kYA on your timeline I become stumped. While you mention the extinction of all of the other "homo" species, you leave us with the impression that there still exists two specific humanoid races; homo-sapien and homo-floresiensis. Following the timeline to it's current point, you never mention the extinction of either species. Is it your theory, then, that there are two distinctly different species of humanoids that now populate the earth? If so, how do I explain this to my children? And how do we tell the difference between who is homo-sapien and who is homo-floresiensis? MOMK9875 01:28, 10 November 2005 (UTC)

Thanks for your question. Homo floresiensis is presumed to be extinct; all humans today are Homo sapiens. H. floresiensis is thought to have become extinct around 12,000 years ago (see Homo floresiensis#Recent survival); after that, Homo sapiens was left as the only surviving human species. Were any to be alive today, you would have no difficulty in differentiating them, as the height of Homo floresiensis is around three feet (one meter). — Knowledge Seeker দ 02:49, 27 November 2005 (UTC)

Does it matter what the creationists think?

Does it matter what the creationists think? I think reference to that in the first para should be removed. I don't see a scientific disclaimer in the book of Genesis either.

Strongly agreed. This article is about a timeline supported by contemporary scientific wisdom. It would be an entirely different matter if there were any evidence at all in favour of young earth Creationism, but there really really isn't. Their objection is purely religious and has nothing to do with fact or the interpretation of fact. Radix 12:17, 29 November 2005 (UTC)

Has the reference been removed already? If so excellent, SqueakBox 14:47, 29 November 2005 (UTC)

Yes, it has, and I agree with its removal as well. — Knowledge Seeker দ 19:45, 29 November 2005 (UTC)

Argh, I was about to suggest this...you beat me to it. Seriously..."potentially incorrect theories"? - 68.33.120.32 01:59, 30 November 2005 (UTC)