Evolution: ask your questions here

[painted wolf]

Thanks PW. I know there are free living organisms that are photosynthetic, such as Euglena. The original questions was why not sentience for plants? My thought is that the combination of events leading to sentience are so rare that it's amazing it happened once (in the branch leading to animals). As you point out, corals and the sea slugs are in symbiotic relationships with photosynthetic organisms, not photosynthetic themselves.

Sorry... I realized my mistake when I checked back a moment ago and saw the rest of the conversation. :faint:
Just a quick cool note about the sea slug... it's not symbiotic, it's a kleptomaniac: it steals chloroplasts from algae it hunts for just that reason.

I'm not sure about your point about needing large amounts of water for photosynthesis. Plants on land require large amounts of water for transpiration and turgor pressure for structure, but I don't think photosynthesis requires more water than an animal's body could hold. After all, isn't the same amount of water proportionally generated by cellular respiration?

As far as I know cellular resperation while it technically produces the same number of molecules of H2O.. the sheer volume of reactions is not enough to produce enough water. Photosynthesis happens on a massive scale within a single leaf. They squeeze in far more chloroplasts than mitochondria. (I could be mistaken, I'm not a botanist)

But ultimately water use for all it's functions is a huge limiting factor for plants.

Sentience would confer to plants the same advantages it has conferred on animals. Animals do not 'need' sentience, but it emerged because, presumably, it gave animals more adaptability, and more adaptability is an evolutionary advantage.

I'm not sure how... plants don't need to chase their food, there is no need to out-think the sun. They get by predators with their pharmacopoeia of toxins and with the help of mutualistic insects like parasitic wasps.

So, I think it was simply due to chance that there are no sentient plants, or photosynthetic, sentient animals.

Maybe, but it could be host of other factors as well... the fact that plants rely on passive water distribution, the way signals are transported across cell membranes and so on.

And who knows, there is still a lot we don't know about plants... we are only just uncovering their abilities to communicate not only with each other but with insects. We have found they are far more dynamic than we once thought... they may yet be 'sentient' in some fashion outside of the animal spectrum.

This may explain, though, why aliens are green.

I thought that was from getting space sick?

wa:do

 

[lunamoth]

Well this is partly evolution, but mostly genetics and I have absolutely no idea what the answer is:
Incest produces offspring with genetic mutations and defects by about the third or fourth generation.
Lab rats are essentially genetic clones but do not lack these defects.
My understanding, which is why I'm probably puzzled, is that in both groups they are sharing the same gene pool when producing offspring, so how/why is it one group is doomed to have genetically mutated offspring that may be pretty bad, but the lab rats it seems are without defect which makes them suitable for genetic testing since they are all the same.

With incest, deleterious recessive alleles are more likely be homozygous. When mixed with the general population, where there are many more copies of the 'normal' allele, expression of the recessive allele is masked in heterozygotes. But, if the recessive allele is in a family, and family members procreate with other family members, the chances of inheriting both recessive alleles is higher.

 

[lunamoth]

Sorry... I realized my mistake when I checked back a moment ago and saw the rest of the conversation. :faint:
Just a quick cool note about the sea slug... it's not symbiotic, it's a kleptomaniac: it steals chloroplasts from algae it hunts for just that reason.

I read that. very cool.

As far as I know cellular resperation while it technically produces the same number of molecules of H2O.. the sheer volume of reactions is not enough to produce enough water. Photosynthesis happens on a massive scale within a single leaf. They squeeze in far more chloroplasts than mitochondria. (I could be mistaken, I'm not a botanist)

Most of the water is passing through the plant, important for long distance transport and support/structure via turgor pressure.

[/quote]But ultimately water use for all it's functions is a huge limiting factor for plants.[/quote]Yes.

I'm not sure how... plants don't need to chase their food, there is no need to out-think the sun. They get by predators with their pharmacopoeia of toxins and with the help of mutualistic insects like parasitic wasps.

Well, those are the strategies they evolved (chemical warfare) in part because of their lack of mobility and nervous system. But, you are probably right, and as auto also said, the sheer abundance of sunlight would reduce the need for a nervous system for food acquisition. It still seems like it would be an advantage when it comes to competition for other limiting factors, or for evasion of predators (strange to think of a cow as a predator, right).

Maybe, but it could be host of other factors as well... the fact that plants rely on passive water distribution, the way signals are transported across cell membranes and so on.

I would postulate that all other other factors would also be very different as well if photosynthetic organisms developed more like animals have. No cell walls, etc..

 

[lunamoth]

As far as I know cellular resperation while it technically produces the same number of molecules of H2O.. the sheer volume of reactions is not enough to produce enough water. Photosynthesis happens on a massive scale within a single leaf. They squeeze in far more chloroplasts than mitochondria. (I could be mistaken, I'm not a botanist)

My Botany text says more than fifty chloroplasts in a very green leaf cell, and several hundred mitochondria per cell, depending upon energy needs of the cell. (Moore, Clark and Stern, 1995).

Just think what might have happened if a primitive cell with properties like Chlamy Chlamydomonas had taken off toward multi-cellular organisms.

Motility, eye-spot, chloroplast...

 

[Autodidact]

I'm still enjoying picturing an oak tree lumbering (so to speak) over to the local pond for a drink.

 

[lunamoth]

I'm still enjoying picturing an oak tree lumbering (so to speak) over to the local pond for a drink.

Har-har. I can't frubal you and I am fresh out of Abba in tin foil.

But I'm humming Waterloo as I type this post.

Added in edit: : hamster :: hamster :: hamster :

 

[painted wolf]

My Botany text says more than fifty chloroplasts in a very green leaf cell, and several hundred mitochondria per cell, depending upon energy needs of the cell. (Moore, Clark and Stern, 1995).

cool... thanks for the info!

Just think what might have happened if a primitive cell with properties like Chlamy Chlamydomonas had taken off toward multi-cellular organisms.

Motility, eye-spot, chloroplast...

Have I mentioned how much I love speculative evolution?
Our "plant-amal" would need very high surface area for photosynthesis to be truly viable as a primary energy source. Perhaps some sort frills?

wa:do

ps. one of my former professors is starting to do research with the photosynthetic sea slugs. She's a botanist, so this she's hoping to bring a different perspective on them.

 

[newhope101]

OOHhh... newhope is play the "like" game again... :jiggy:

if the footprints are "bird-like" then they must be made by "fully formed birds"... therefore any "bird-like" footprints must be made by birds.
Well that sounds good PW. However your researchers classified these footprints as 'unknown therapods', a dino with bird characters. Why? Because they predate the dinos they were meant to have evolved from. Hence the footprints can more appropriately been seen as proof that birds were created and did not evolve from another kind. Again you appear to purport to know more than your leading researchers which I doubt.
Say hello to this bird:

He left lots of bird-like footprints in the late Triassic. So it's only "common sense" that it's a bird.
Thanks for proving dinosaurs are birds newhope!
Again PW you try to show black and white. This in itself illustrates a lack of acceptance and knowledge of the state of your science.
As for the "mystery" of the Platypus...
1) you don't need to be fully endothermic to need to cool off. Even reptiles risk overheating, evolving something as simple as sweating would be a huge benefit and a good step toward full endothermy.
Plus not that all mammals are good endotherms, many... like the platypus, are very poor at controlling their body temperature. Many reptiles are very good at controlling their body temperatures, crocodiles especially.
So what?
2) Because adding lipids to the water slows it's evaporation... cutting down on the work needed from the parent. It's not a difficult concept and it''s not as if it's unique... desert amphibians can do it too.
So what?
3) platypus are not the only venomous mammals, venom is common to all vertebrate groups. Plus they also have less advanced fossil ancestors with less developed bills. And the Platypus genome shows it's place in the mammal lineage... not with birds, not with reptiles.
So what
wa:do

All you have done is speak to 'commonly accepted' ideas.


Because of the early divergence from the therian mammals and the low numbers of extant monotreme species, the platypus is a frequent subject of research in evolutionary biology. In 2004, researchers at the Australian National University discovered the platypus has ten sex chromosomes, compared with two (XY) in most other mammals (for instance, a male platypus is always XYXYXYXYXY),[58] although, given the XY designation of mammals, the sex chromosomes of the platypus are more similar to the ZZ/ZW sex chromosomes found in birds.[59] The platypus genome also has both reptilian and mammalian genes associated with egg fertilisation.[60] Since the platypus lacks the mammalian sex-determining gene SRY, the mechanism of sex determination remains unknown.[61] A draft version of the platypus genome sequence was published in Nature on 8 May 2008, revealing both reptilian and mammalian elements, as well as two genes found previously only in birds, amphibians, and fish. More than 80% of the platypus' genes are common to the other mammals whose genomes have been sequenced.[60]
http://en.wikipedia.org/wiki/Platypus

I am so glad you have worked it all out PW. Now you need to go inform your researchers, because they are still confused.

 

[newhope101]

I'd like to request some information relating to an article. The article appears to make a case that researchers have no clue in relation to the ancestry of mammals. I support it. What do you all have to say about it...preferably with accompanying evidence and preferably that is not purley based on assumptions and huge leaps of faith.

Please shed some light on the following questions and assertions within this article relating to the platypus and monotremes:
Truth In Science - Platypus: a Darwinian Cautionary Tale

So we have a few questions:
1. For the lactation machinery to evolve from a sweat gland there has to be a functioning sweat gland but reptiles [and birds] do not possess sweat glands. There is no requirement for sweat glands until the animal has evolved an endothermic physiology. In other words, a mammal has to be a mammal to possess a sweat gland.

2. Since sweat is 99% water, why was it deemed necessary to evolve all the milk protein coding genes just to keep the eggs cool? It is worth noting that milk has no nutritional benefit for a developing embryo encased in the monotreme egg.If, as Professor Wolpert and others suggest, lactation in the platypus is the beginning of the evolution of the breast [presumably the nipple and the machinery associated with it], one has to assume that all the ancient mammals from the mid-Triassic to the Cretaceous had monotreme-like oviparous physiology even though there is no fossil evidence to suggest that this is true. The general Darwinian consensus [also reflected in the Nature paper on the platypus genome] is that the monotremes diverged from the other mammals approximately 166 million years ago.
Nevertheless, the oldest known fossils recognisable as monotremes include Teinolophos trusleri, Steropodon galmani and Kollikodon ritchiei. These creatures are conventionally dated at approximately 100 to120 million years, supposedly 100 million years after the emergence of true mammals in the fossil record in the late Triassic.

So was Castorocauda an ancient monotreme? According to Kemp, “the solution to the mystery of the monotremes continues to be elusive”. Presumably, this will remain the situation until there is some major revision in current Darwinian thinking.


In other words, the brain of the monotreme is specifically wired to enable the creature to perform its remarkable abilities. It is not at all surprising therefore, following the publication of the platypus genome, that this uniqueness is reflected in the genes of this amazing creature. In fact, whatever the platypus does, it will require the genes to enable it to do so. It is like a bird as it lays eggs. It is like a reptile as it produces venom. It is a warm blooded fur-covered mammal producing milk to suckle its young. It has a unique electro-sensory system and can detect odours and pheromones underwater with unparalleled sensitivity. It is worth noting that the other main group of vertebrates that rely of electroreception are fish and sharks in particular!

The platypus will remain a significant misfit in any Darwinian scheme.

Is it from a sauropsid lineage which includes reptiles and birds?
Is it from a synapsid lineage which supposedly led to the emergence of the mammals?
Or is it derived independently from some unknown ancestral amniote? Or could it be that the Darwinian hypothesis, cladistic analysis or any other classification system for that matter is just far too restrictive?

Without doubt, there are mammal-like reptiles as there are reptile-like mammals. The platypus is a Darwinian cautionary tale. Is it a bird or is it a plain … old platypus?



...and just a kind that is not decendant from anything. What do you all think?

Still no one has answered the above questions. Neither will any of you be able to speak to answers. The reason being your leading researchers are still in debate about these questions and PW is unable to answer from any scientific base other than one she chooses to align with....which means nothing much in the grand scheme of things.

 

[painted wolf]

Newhope, it's not my fault you can't understand or flat out refuse to acknowledge the comments I give.

Yet again we simply see newhope doing the usual...:ignore:
then pretending that their questions are brilliant beyond the realm of science.

wa:do

 

[newhope101]

OOHhh... newhope is play the "like" game again... :jiggy:

if the footprints are "bird-like" then they must be made by "fully formed birds"... therefore any "bird-like" footprints must be made by birds.
Thanks for confirming the footprints apear to be plain old bird footprints
Say hello to this bird: No below is not a bird. Dinos are not aves..Remember!


Cladistics - Wikipedia, the free encyclopedia

He left lots of bird-like footprints in the late Triassic. So it's only "common sense" that it's a bird.
Thanks for proving dinosaurs are birds newhope! Rather thankyou for confirming the footprints are plain old bird footprints. Unfortunately your researchers say they cannot be true birds but must be a therapod dino. I agree with you..these were plain old bird footprints and birds predate the first known birdlike therapods by 55 million years. Hence it appears that birds did not evolve from these therapod dinosaurs. Researchers require these footprints to not be birds, which you and I agree are birds, as they blow current theories out the window. Why do you think 'few scientists' would say these are plain old bird footprints? Because it does not line up with current thinking.

There exist documented tracks that appear avian since the Late Triassic, by some 55 million years predating the first proper evidence that very birdlike theropods were present. The Late Triassic and early-mid Jurassic tracks have been assigned to the ichnogenera Trisauropodiscus and Aquatilavipes. Few scientists would go as far though to consider these traces evidence that birds evolved much earlier than generally believed, and perhaps not from theropod dinosaurs as per today's mainstream opinion.
Bird ichnology - Wikipedia, the free encyclopedia
As for the "mystery" of the Platypus...
1) you don't need to be fully endothermic to need to cool off. Even reptiles risk overheating, evolving something as simple as sweating would be a huge benefit and a good step toward full endothermy.
Plus not that all mammals are good endotherms, many... like the platypus, are very poor at controlling their body temperature. Many reptiles are very good at controlling their body temperatures, crocodiles especially.
Both the terms "warm-blooded" and "cold-blooded" have fallen out of favour with scientists because of the vagueness of the terms and an increased understanding of the field. Body temperature types are not discrete categories. Each term may be replaced with one or more variants, see the next section for examples. Body temperature maintenance (thermoregulation) incorporates a wide range of different techniques that result in a body temperature continuum, with the traditional ideals of warm-blooded and cold-blooded being at opposite ends of the spectrum.
Warm-blooded - Wikipedia, the free encyclopedia
2) Because adding lipids to the water slows it's evaporation... cutting down on the work needed from the parent. It's not a difficult concept and it''s not as if it's unique... desert amphibians can do it too.
See above link. This is not as black and white as you purport!
3) platypus are not the only venomous mammals, venom is common to all vertebrate groups...but not mammals Plus they also have less advanced fossil ancestors with less developed bills. And the Platypus genome shows it's place in the mammal lineage... not with birds, not with reptiles. Yet it has 10 sex chromosomes like a bird... It is about the platypus have a mosaic of traits.

The bizarre appearance of this egg-laying, venomous, duck-billed, beaver-tailed, otter-footed mammal baffled European naturalists when they first encountered it, with some considering it an elaborate fraud. It is one of the few venomous mammals; the male platypus has a spur on the hind foot that delivers a venom capable of causing severe pain to humans. The unique features of the platypus make it an important subject in the study of evolutionary biology and a recognisable and iconic symbol of Australia;
Platypus - Wikipedia, the free encyclopedia
wa:do

Because of the early divergence from the therian mammals and the low numbers of extant monotreme species, the platypus is a frequent subject of research in evolutionary biology. In 2004, researchers at the Australian National University discovered the platypus has ten sex chromosomes, compared with two (XY) in most other mammals (for instance, a male platypus is always XYXYXYXYXY),[58] although, given the XY designation of mammals, the sex chromosomes of the platypus are more similar to the ZZ/ZW sex chromosomes found in birds.[59]

They are conventionally treated as comprising a single order Monotremata, though a recent classification[20] proposes to divide them into the orders Platypoda (the platypus along with its fossil relatives) and Tachyglossa (the echidnas, or spiny anteaters). The entire grouping is also traditionally placed into a subclass Prototheria, which was extended to include several fossil orders, but these are no longer seen as constituting a natural group allied to monotreme ancestry. A controversial hypothesis now relates the monotremes to a different assemblage of fossil mammals in a clade termed Australosphenida.[7][21]




So again I am glad you have it all worked out PW because your researchers as yet, have not. The best you can do is reflect the 'common view' which does not address much of the controversy.

..and again thankyou for confirming late triasic plain old bird footprints, that are 'of course' bird footprints, actually predate the therapod dinosaurs they are meant to decent from. Hence birds appear fully formed and not decendant from anything thus far.....the bird footprints proves it. The theories around the footprints being anything other than plain old ordinary birds is theorised to keep the status quo re birds from tumbling.

 

[camanintx]

So again I am glad you have it all worked out PW because your researchers as yet, have not. The best you can do is reflect the 'common view' which does not address much of the controversy.

And yet none of this does anything to refute the Theory of Evolution. It's like we have 100 pieces of a 10,000,000 piece puzzle in place and since we don't know exactly where the other 99,999,900 go yet you're saying it's a mosaic instead of a puzzle.

 

[painted wolf]

Yet more evidence newhope hasn't got a clue... just had to have another go didn't you?

Wiki quote mining.... which does nothing to make your contention that anything that makes "bird-like" footprints must be a bird less silly. I've given you an example of something that makes "bird-like" footprints that isn't a bird. And you still don't grasp that but keep insisting on it.

Your ignorance of the plethora of three toed critters running around that arn't birds from the time period is not my problem.

I never used the words "warm-blooded" or "cold-blooded" I pointed out why your assumption of endothermy being necessary for sweating was wrong because endothermy isn't a definitive state. Thank you for agreeing with me on this and admitting you were wrong though.

However that has nothing to do with how adding lipids to water to keep eggs cool is impossible. It's a non-sequitor. Again, I'm not responsible for your ignorance... you choose to dismiss what I have to say off-hand and thus look a fool, that is up to you.

Yes, there are several mammals that are poisonous.... venom is found in shrews, solenodons, prosimians, moles and others.

Platypus have an XY system.... yes, they have more chromosomes in determining sex than we do... but they are unlike birds who don't have X and Y chromosomes... Birds have Z and W chromosomes that determine sex and in some birds it's also just two chromosomes. Again, you don't seem to be able to grasp the concept of "like".

Quoting how people from hundreds of years ago were confused by the platypus doesn't help you look any less confused about them.

Finally repeating yourself and then engaging in ad hominem attacks against me and science in general, further reduces your stance.

Let me know when you actually want to contribute sometime, rather than attempt to derail threads with nonsense.

wa:do

 

[newhope101]

OOHhh... newhope is play the "like" game again... :jiggy:

if the footprints are "bird-like" then they must be made by "fully formed birds"... therefore any "bird-like" footprints must be made by birds.

Say hello to this bird:

He left lots of bird-like footprints in the late Triassic. So it's only "common sense" that it's a bird.
Thanks for proving dinosaurs are birds newhope!
But are they Paintedwolf? You have been unable to defend your position on other threads. Why do you think birds decended from dinos? Do pleae give your articulation of the robustness from conflicting research.
As for the "mystery" of the Platypus...
1) you don't need to be fully endothermic to need to cool off. Even reptiles risk overheating, evolving something as simple as sweating would be a huge benefit and a good step toward full endothermy.
Plus not that all mammals are good endotherms, many... like the platypus, are very poor at controlling their body temperature. Many reptiles are very good at controlling their body temperatures, crocodiles especially.

2) Because adding lipids to the water slows it's evaporation... cutting down on the work needed from the parent. It's not a difficult concept and it''s not as if it's unique... desert amphibians can do it too.

3) platypus are not the only venomous mammals, venom is common to all vertebrate groups. Plus they also have less advanced fossil ancestors with less developed bills. And the Platypus genome shows it's place in the mammal lineage... not with birds, not with reptiles.

wa:do

Indeed I suggest rather stongly, that you, Paintedwolf, will be unable to defend your position in relation to the ancestry of birds in relation to other research that suggests birds did not evolve from dinosaurs. Go for it. You were unable to articulate an answer previously and you will likewise be unable to defend yourelf here.
Discovery Raises New Doubts About Dinosaur-bird Links

 

[outhouse]

could you not! keep posting trash newhope???????????????

 

[newhope101]

Outhouse... after the defamation leveled my way with archaeopteryx and the like, I have no problem in requesting those that shoved it in my face being able to defend their position as to whether or not the dinosaur is actually the true ancestor of birds.

So 'bird like' footprints may have had nothing to do with dinos and all your arch evidence many pushed and shoved, might just be woffle. How unfortunate for evolutionists!

Evolutionists say they have evidence of the bird from dino ancestry. Now defend it against this contradicting research? People deserve the full body of information and not just what appears to be convenient.


Discovery Raises New Doubts About Dinosaur-bird Links

 

[Autodidact]

Outhouse... after the defamation leveled my way with archaeopteryx and the like, I have no problem in requesting those that shoved it in my face being able to defend their position as to whether or not the dinosaur is actually the true ancestor of birds.

So 'bird like' footprints may have had nothing to do with dinos and all your arch evidence many pushed and shoved, might just be woffle. How unfortunate for evolutionists!

Evolutionists say they have evidence of the bird from dino ancestry. Now defend it against this contradicting research? People deserve the full body of information and not just what appears to be convenient.


Discovery Raises New Doubts About Dinosaur-bird Links

It's really a pretty simple concept. Are you unable to understand, or unwilling?

It makes no difference to the Theory of Evolution whether birds evolved from dinosaurs or not. ToE does not rest on the specific evolutionary pathway of birds. It rests on literal mountains of evidence, and if there were no such thing as birds or dinosaurs, it would still be correct.

So if you are invested in a particular hypothesis regarding bird evolution, I suggest you start a thread to discuss it. Neither I nor painted wolf is wedded to any particular hypothesis, which in any even has no bearing on the subject here.

 

[newhope101]

Autodidact Quote:
It's really a pretty simple concept. Are you unable to understand, or unwilling?
Well if it is so simple explain it.
It makes no difference to the Theory of Evolution whether birds evolved from dinosaurs or not. ToE does not rest on the specific evolutionary pathway of birds. It rests on literal mountains of evidence, and if there were no such thing as birds or dinosaurs, it would still be correct.
I know it makes no difference to you, uou will believe what you are told without even understanding it, yet you and PW portray yourselves to be biologists.
So if you are invested in a particular hypothesis regarding bird evolution, I suggest you start a thread to discuss it. Neither I nor painted wolf is wedded to any particular hypothesis, which in any even has no bearing on the subject here.
Why should I. This is an "ask a biologist" thread and I have found a question you and PW are unable to speak to.

I'll say it again another way. If you are unable to defend the bird from dino ancestry that you shove in our faces as irrefuteble evidence for evolution then you should understand why it is regarded as evidence.

You should be so convinced of arch and his mates that you can instantly refute any other assertation to the contrary.

Has anyone done so? No.

Is anyone going to? No..just pitifull excuses as to why you wont..meaning of course neither of them are able to answer and defend their stance.

Discovery Raises New Doubts About Dinosaur-bird Links





During walking and running in birds, hindlimb movement is generated primarily at the knee and ankle joints; in humans, movement occurs at the knee, ankle and hip joints. The bird's thigh does not move substantially from its nearly horizontal position where it provides rigid lateral support to the thin walled air-sacs of the respiratory system. (Credit: Image courtesy of Oregon State University)

It would appear that if either Paintewolf or Autodidact knew their stuff as much as they pretend to this article should be easy to speak to or refute.

Punch "Archaeopteryx," into the RF search to see how many times these guys have shoved this evidence in creationists faces and laughed at them and called us stupid for not blindly accepting this evidence.

Let me provide a response to your, or any evos, next reply:

More excuses, asides, belittling and dribble with NO articulation in response to contradicting research related to bird ancestry. You both are unable to answer, and this is clearly the fact that creationists need to remember in the future.

 

[outhouse]

could you not! keep posting trash newhope???????????????

what part of YOU dont understand, do you not get.

you lack education

 

[newhope101]

And just as predicted ...Still, not one of you can defend their stance on the ancestry of birds, just many pretenders here without any clue about what they refer to as evidence.

Discovery Raises New Doubts About Dinosaur-bird Links