The Scientific Method & Macroevolution?

[justlookinla]

Pardon?

What?

 

[crjmurray]

Bacteria evolve into.....bacteria?

Is there a point to this? Is it in response to something?

In the South we use pardon as a question usually in an attempt to clarify something. So again...

Pardon?

 

[justlookinla]

Is there a point to this? Is it in response to something?

In the South we use pardon as a question usually in an attempt to clarify something. So again...

Pardon?

Just making an observation, thus just a general statement concerning evolution.

 

[crjmurray]

Just making an observation, thus just a general statement concerning evolution.

Oh. Well thank you for your contribution to the conversation. There's a thread I started you might be interested in. Feel free to check it out and contribute there as well.

 

[Loudmouth]

organism, a symbolic representation of any and all life.
species, a specific kind of organism.
what's so hard about that?

Chihuahua is a specific kind of organism. Are chihuahuas a species?

this is an assumption.
it's a good, reasonable guess, but that's all it is.

It isn't assumed. It is seen in living populations and in the fossil record.

it's really hard to choose which absurdity:
there is a god, or things becoming alive.
please, don't start with the abiogenesis bit.

Why is it so absurd to accept the OBSERVATIONS that offspring are born with mutations, and those mutations pass through natural selection?

 

[lewiscalledhimmaster]

Quite literally, the definition of proven beyond a reasonable doubt.

Even Pope Francis agrees, but there is always the important matter of falsifiability -- right?

 

[PsychoSarah]

Just making an observation, thus just a general statement concerning evolution.

Prokaryotic cells give rise to more prokaryotic cells. Eukaryotic cells did not evolve from prokaryotic ones; prokaryotes and eukaryotes share an ancestor that preceded both groups.

 

[AV1611VET]

prokaryotes and eukaryotes share an ancestor that preceded both groups.

Only on paper.

 

[PsychoSarah]

Only on paper.

My point is that we didn't evolve from bacteria, and given the differences between eukaryotic and prokaryotic cells and the fact that eukaryotic cells got to multicellular organisms faster, you won't be seeing many multicellular prokaryotes.

 

[AV1611VET]

My point is that we didn't evolve from bacteria, and given the differences between eukaryotic and prokaryotic cells and the fact that eukaryotic cells got to multicellular organisms faster, you won't be seeing many multicellular prokaryotes.

I wouldn't know.

All that stuff is over my head.

 

[PsychoSarah]

I wouldn't know.

All that stuff is over my head.

That's why I am the one telling you

 

[lewiscalledhimmaster]

My point is that we didn't evolve from bacteria, and given the differences between eukaryotic and prokaryotic cells and the fact that eukaryotic cells got to multicellular organisms faster, you won't be seeing many multicellular prokaryotes.

Good morning Sarah,

Would you be so kind as to unpack the science a bit for my musty old brain cells are hungry to learn?

Thanks,
Lewis.

 

[PsychoSarah]

Good morning Sarah,

Would you be so kind as to unpack the science a bit for my musty old brain cells are hungry to learn?

Thanks,
Lewis.

Of course.

So, prokaryotic cells, such as bacteria, are actually far more successful, in terms of evolutionary fitness, thanks to their fast generation time (it can be within 4 hours in really good conditions) allowing them to quickly adapt to changes in the environment. No matter what the conditions, chances are at least 1 bacterium within a population will be capable of suviving, and that is all that is needed in order to reestablish a population which is capable of surviving in the new conditions. Even better, individual bacteria can be very mobile and have chemical triggers to avoid deadly conditions and move towards favorable ones, which is a lot easier to do singularly rather than communally.

Being multicellular has its advantages as well, but prokaryotic cells do not have an advantage over eukaryotic cells in becoming multicellular. For one thing, they lack mitochondria, an energy producing organelle which eukaryotic cells have that allows them to have higher and faster energy processing than prokaryotes. Additionally, eukaryotic cells are generally far larger than prokaryotic cells, and seeing as one of the big advantages to being multicellular is avoiding being consumed, it would take far more prokaryotic cells to make an organism the same size as one made of eukaryotic cells. They do, in a way, take advantage by living in the bodies of multicellular eukaryotic organisms, but they retain being unicellular.

But it really is that energy production that places eukaryotes as becoming multicellular over prokaryotes. The way multicellular organisms work is through the specialization of cells to perform various functions at the cost of not being able to perform all the functions needed for survival by themselves. This requires the energy processing cells to be able to produce enough not only for themselves, but for a great number of other cells as well. Prokaryotic cells just don't have the capacity to do that to the extent eukaryotic cells can in a natural environment, and being that they were already dominating the single celled life, natural selection pressures didn't push prokaryotes to become multicellular.

Is this what you were looking for?

 

[whois]

Chihuahua is a specific kind of organism. Are chihuahuas a species?

yes, a species that all chihuahuas belong to.

It isn't assumed. It is seen in living populations and in the fossil record.

regardless of what you may think, it has never been demonstrated that plants can turn into animals, or animals can turn into plants.

Why is it so absurd to accept the OBSERVATIONS that offspring are born with mutations, and those mutations pass through natural selection?

there is nothing at all wrong with accepting adaptation or heredity.

 

[lewiscalledhimmaster]

Is this what you were looking for?

Yes thanks, Sarah, this is exactly what I was looking for. I haven't read it yet, but as soon as I have allowed it to collide with my grey-matter -- I'll try to get back before someone who processes stuff quicker than I do.

Thanks again,
Lewis

 

[Loudmouth]

yes, a species that all chihuahuas belong to.

Are chihuahuas and great danes separate species? If not, why not?

regardless of what you may think, it has never been demonstrated that plants can turn into animals, or animals can turn into plants.

No one thinks that animals evolved from plants.

there is nothing at all wrong with accepting adaptation or heredity.

You seem to have a problem with accepting adaptation through accumulating mutations and selection.

 

[lewiscalledhimmaster]

Are chihuahuas and great danes separate species? If not, why not?

Funny you should bring the subject of Chihuahuas and Great Danes. I was thinking about them too. Wasn't this also addressed on my 'Lines Of Evidence' thread?

No one thinks that animals evolved from plants.

This reminds me of the sort of thing which Kent Hovind was harping on about (with his 'butterflies'), in his radio discussion with Prof. Eugenie Scott.

http://www.youtube.com/watch?v=H7XUsgat1j0

 

[lewiscalledhimmaster]

Of course.

So, prokaryotic cells, such as bacteria, are actually far more successful, in terms of evolutionary fitness, thanks to their fast generation time (it can be within 4 hours in really good conditions) allowing them to quickly adapt to changes in the environment. No matter what the conditions, chances are at least 1 bacterium within a population will be capable of suviving, and that is all that is needed in order to reestablish a population which is capable of surviving in the new conditions. Even better, individual bacteria can be very mobile and have chemical triggers to avoid deadly conditions and move towards favorable ones, which is a lot easier to do singularly rather than communally.

How would that 1 bacterium reestablish a population?

 

[whois]

You seem to have a problem with accepting adaptation through accumulating mutations and selection.

correct.
i have seen no indication that bats were anything other than bats, they always have been, and they will always be.

the commonality of DNA makes it easy to come up with "similarities" that aren't reality.
there can easily be 2 different organisms that displays enough similarities to assume one came from the other when in fact nothing like that happened.

the "mutations" of which you speak, most of these are transposons.
the "mutations" that matter take place in our HOX genes, and are responsible for some of our nastiest deformities.
they are responsible for the majority of miscarriages, and they are responsible for some cancers.
in my opinion, these types of mutations will not accumulate, but instead result in a profound change in the organism.
just a few of these mutations will result in a non viable organism.
this implies that each organism has a unique HOX pattern that cannot be breached.

 

[lewiscalledhimmaster]

correct.
i have seen no indication that bats were anything other than bats, they always have been, and they will always be.

Are you a vampire? / Leave the bats alone, already.

As the hot shot scientists (though not all here are) are currently enjoying the grace of Easter holidays, I'm going to delve into the dark corridors of Wikipedia and give you a little of what is provided freely for anyone who wants to know:

'....Little fossil evidence is available to help map the evolution of bats, since their small, delicate skeletons do not fossilize very well. However, a Late Cretaceous tooth from South America resembles that of an early microchiropteran bat. Most of the oldest known, definitely identified bat fossils were already very similar to modern microbats. These fossils, Icaronycteris, Archaeonycteris, Palaeochiropteryx and Hassianycteris, are from the early Eocene period, 52.5 million years ago.[17] Archaeopteropus, formerly classified as the earliest known megachiropteran, is now classified as a microchiropteran.

Bats were formerly grouped in the superorder Archonta along with the treeshrews (Scandentia), colugos (Dermoptera), and the primates, because of the apparent similarities between Megachiroptera and such mammals. Genetic studies have now placed bats in the superorder Laurasiatheria, along with carnivorans, pangolins, odd-toed ungulates, even-toed ungulates, and cetaceans.[1] A recent study by Zhang et al. places Chiroptera as a sister taxon to the clade Perissodactyla (which includes horses and other odd-toed ungulates).[29] However, the first phylogenomic analysis of bats shows that bats are not sister to Perissodactyla, and instead are sister to a larger group including ungulates and carnivores.[20] ....' *

~~~
17. http://adsabs.harvard.edu/abs/2008Natur.451..818S /
https://www.ncbi.nlm.nih.gov/pubmed/18270539

1. http://mbe.oxfordjournals.org/content/22/9/1869 / http://www.nature.com/nature/journal/v451/n7180/full/nature06549.html / https://www.ncbi.nlm.nih.gov/pubmed/15930153

29. http://www.sciencemag.org/content/339/6118/456

20. http://www.cell.com/current-biology...m/retrieve/pii/S0960982213011305?showall=true / https://www.ncbi.nlm.nih.gov/pubmed/24184098

* - click through for the chart etc. (plenty to read and study) : https://en.wikipedia.org/wiki/Bat#Classification_and_evolution