winstonjen

WRONG! Natural selection picks those organisms that will survive most successfully in their environment. Most successfully means that they will be in balance with their environment, and multiply. Success also implies a sense of ease - less suffering with each passing generation.

And of COURSE death is needed - the world would get overpopulated with all kinds of creatures otherwise. :banghead:

Fiach

I can't believe that Ed and other people say such a thing as "if evolution is true." It is inescapable, a proven fact. We now have not only fossils as multiple stages of development at various epochs of million year periods and eras. This is confirmed by the isotope dating, the correlation of that with the rates of sea floor spreading and continental drift. Plate tectonic is a fact. The velocity of the continents can be measured by satellite laser at 2 cm per year.

That velocity divided into the distance Europe-Africa and the Americas from the mid Atlantic rift gives approx. 240 million years which is the date of the igneous rocks on opposite sides of the Atlantic in Kameroons and Brazil.

Now genetic information from the Human Genome and related non-human genomes confirms evolution like a molecular textbook. We carry the old relic genes of Cambrian ancestors. The gene for a arthropod shell is still in our nuclei. Occasionally it expresses and causes a human baby to grow a lobster like chitonous shell. We all in the embryo pass through a chordate stage develop a notochord not found in adult vertebrates but found in primitive amphioxus. We go through fish stages with gill slits, and amphibian stage with lobe fins developing into limbs. We temporarily have a tail that absorbs, but an occasional baby has a tail. The Gill slits get recycled into ear and laryngeal parts. But sometimes part persists and a human baby is born with a partial gill, technically and politically correctly called a branchial cleft cyst. But what it is is gill tissue.

Evolution is all around us. Our embryonic development is a movie strip of our evolution. Our genome (nucleotide codes) is a history text of our evolution. Denial of this important core fact of biological science is wishful thinking. Evolution and the knowledge it spurs has made great medical breakthroughs, that Magical Creation never promised.

Fiach

Fiach

Death is essential. If organisms didn't die, DNA would not mutate in the offspring, and evolution could not have occurred. The world would get overpopulated, food sources would be insufficient unless living organisms lived on sand and gravel.

Fiach

winstonjen

And it is truely saddening to observe someTHING like Ed here develop from evolution. :boohoo:

Hopefully Natural Selection will do its little bit.

NOGO

Ed, what have you read, "BB theory for kindergaden students".

BB Theory does not say that matter and space time came into being at a point in time. We simply have no way of knowing that. The universe did start expanding at some point in time and is continuing to expand and we do have evidence for that.

The Bible also says that the earth existed before the sun and stars which is completely contrary to BB theory.

Ed, this is yet another example where you ignore evidence. You only take what you want, what fits into your preconceived beliefs and ignore the rest.

What Genesis says has absolutely nothing to do with BB theory.

Fiach

Careful Mate, for coments a bit more caustic than that I may soon be kicked off of this forum. In fact, Jobar may TOSS me any moment now.

Fiach

lpetrich

Not quite correct. Mutations will occur no matter what.

As to death, there are a number of basic causes.

A simple one is that organisms are not indestructible. Being eaten by predators is an example of this mechanism.

Another is lack of resources, such as lack of food or light or whatever -- a lack that may be caused by overpopulation. Darwin noted that even slow reproducers can out-reproduce the carrying capacity of their environment given enough time.

Some other reasons come into play in multicellular organisms; single-celled ones multiply by dividing, and disappear into their offspring.

When an organism has done enough reproduction so that its genes will be represented in future generations, it may no longer have much selection pressure to stay alive. Thus, it can accumulate late-acting genetic defects.

Also, an organism can compete with its offspring for resources; death may be a way of getting itself out of the way to allow other possessors of its genes to flourish.

There is some evidence for that last possibility. Some flowering plants have a tendency to stop producing flowers, and even to die, after they "go to seed". Thus, one way of keeping them alive and flowring is to keep them from doing that -- and they will be tricked into concluding that they have not reproduced. Which can be done by cutting off their old flowers that have started to produce seeds.

lpetrich

Fiach:
We now have not only fossils as multiple stages of development at various epochs of million year periods and eras. ...

(continental drift...)

Observed vs. extrapolated drift rates agree very well for most continental-plate motions, and not simply South America vs. Africa. I wonder if there is some earth-science counterpart of PubMed. or ArXiv, two collections of abstracts and other such professional-literature stuff.

Also, different radioisotopes consistently give the same date for the same rock, meaning that their radioactive-decay constants have stayed constant over geological time, or else have varied in exact synchronization.

Now genetic information from the Human Genome and related non-human genomes confirms evolution like a molecular textbook.

Actually, the Genomes On-Line Database (GOLD) lists 129 genomes sequenced, the large majority of which are of prokaryotes -- one-celled organisms without distinct cell nuclei. Those with eukaryotic cells that have been sequenced are:

Human Homo sapiens
Mouse Mus musculus
Sea Squirt Ciona intestinalis
Fruit Fly Drosophila melanogaster
Malaria Mosquito Anopheles gambiae
Nematode Caenorhabditis elegans
Brewer's Yeast Saccharomyces cerevisiae
Fission Yeast Schizosaccharomyces pombe
Small Mustard Weed Arabidopsis thaliana
Rice Oryza sativa
Malaria Microbe (human) Plasmodium falciparum (rodent) Plasmodium yoelii yoelii
Microsporidian Encephalitozoon cuniculi

And numerous genes have been sequenced from a variety of organisms; there is a huge database of gene sequences over at PubMed.


We carry the old relic genes of Cambrian ancestors.

And further -- it's been possible to reconstruct several of the genes that were possessed by the common ancestor of all of existing life. It had RNA-to-protein translation, DNA-RNA transcription, lots of biosynthesis capabilities, but only poorly-developed DNA replication. It was likely autotrophic, like a plant, but chemosynthetic, living off of various chemical reactions, like H2 + S -> H2S.

The gene for a arthropod shell is still in our nuclei. Occasionally it expresses and causes a human baby to grow a lobster like chitonous shell.

That's male-bovine excrement. I've never heard of such a thing, and our species is NOT descended from some arthropod one. Evolution works like a tree, and NOT like a ladder.

We all in the embryo pass through a chordate stage develop a notochord not found in adult vertebrates but found in primitive amphioxus.

That's correct. But the Amphioxus gets its notochord growing into its head.

We go through fish stages with gill slits,

And a fishlike circulatory system, including aortic arches for the gills and a two-chambered heart. However, an early embryo is NOT a "complete" fish.

and amphibian stage with lobe fins developing into limbs.

Sort-of correct; fin and limb anatomy are closely related.

We temporarily have a tail that absorbs, but an occasional baby has a tail.

That's a good one.

The Gill slits get recycled into ear and laryngeal parts. But sometimes part persists and a human baby is born with a partial gill, technically and politically correctly called a branchial cleft cyst. But what it is is gill tissue.

Quite correct. And the really interesting thing is that some land vertebrates have had descendants that have become completely aquatic, like ichthyosaurs, sirenians, and cetaceans. Dolphins and whales are stuck with having to breathe air, however convenient it might be for them to breathe water on occasion.

Also, cetacean blowholes are their nostrils -- their nostils have moved from the front to the top of their heads, and we can see intermediate stages in various fossil cetaceans. Also, present-day cetaceans have relatively large heads; such fossil cetaceans as Zeuglodon have much smaller heads relative to body size -- more like most land mammals.

Cetaceans also have a nice way of being able to breathe, one that gets around a certain shared limitation. Their trachea opens from their esophagus ventrally, toward their belly, as is typical for land vertebrates. Which is the "wrong" side for reaching the nostrils. So their trachea extends up into the nasal cavities, making the eating path and the breathing path non-intersecting. A designer that can design from scratch may surely be able to avoid constructing kludges of this nature.

So if living things were created, they were created with the appearance of being the result of evolution.

lpetrich

As to the Big Bang, Stephen Hawking's Singularity Theorems allow us to determine what sort of origin it must have had. These theorems state that if:

Gravity is classical General Relativity
The matter-energy content satisfies certain reasonable conditions
Certain starting configurations of some material

Then the material will collapse to a "singularity", a point with infinite density.

The Big Bang, however, is gravitational collapse going backward, so we conclude that if all these conditions are satisfied, we ought to get a singularity.

BUT, is gravity classical all the way? One can calculate the size scale at which quantum fluctuations of space-time are big enough to make black holes, and get the "Planck distance", where quantum-gravity effects will be strong.

So classical gravity is a reasonable approximation only for length scales greater than the Planck length, about 10^-34 m.

And when the Universe had a distance scale of a Planck length, quantum-gravity effects were strong, contrary to Hawking's Singularity Theorems.

But idespite some heroic efforts, it has been difficult to find a theory of quantum gravity that:

1. Is mathematically self-consistent at all length scales
2l Can predict the nongravitational Standard Model of particle physics with a minimum of kludges and ad hoc assumptions

The usual methods of quantum field theory have trouble with #1 at length scales less than the Planck mass, where quantum-gravitational effects are strong.

It is possible to ameliorate this difficulty by adding some extra elementary-particle fields, but the only success in doing so has been a line of theorizing called "superstrings", which effectively posits an infinite number of such fields that are specified in a certain fashion.

Though gravity works out OK in superstring theory, it is difficult to satisfy #2 without adding some extra assumptions, like that the Universe has 4 big space-time dimensions and 6 very tiny space dimensions, with those tiny dimensions having a certain topology.

So we've run into some theoretical Terra Incognita.

Fiach

First they debated about the amount of dark matter and (believe it or not) dark energy that could tip the scales for an ever expanding universe or one that will reach maximum then start the long reverse collapse to the singularity.

Now they are saying in (Scientific American or Discovery) that a repulsive force exists like a reverse or negative gravity. And that this is sufficient to keep the universe ever expanding. So much is theoretical with fancy math equations with Greek symbols that drive one barmy. Conclusion is that we don't know.

Fiach