Arete

Any substance that causes mutation is a "mutagen" http://en.wikipedia.org/wiki/Mutagen . By definition, the potent ones are also usually pretty dangerous things too and not the sort of thing you can generally use safely at home. Worker ants, the ones you see out and about at home are sterile. Even if you could mutate them, they don't have offspring. While a nice idea, your experimental design needs work.

As an arm-waving generalized hypothesis, yes. If you want to take selection through environmental variation further, empirical demonstration of how a particular environmental parameter causes a selection for a particular phenotypic trait is necessary and particularly pertinent when suggesting sympatric, ecologically driven speciation. For example - Darwin's finches, parallel evolution of limetic and benthic stickleback, the cichlid radiation, Caribbean anoles etc. see http://www.sciencedi...169534709001268 for a nice summary piece. Otherwise, stochastic genetic drift in allopatry can explain phenotypic diversity in the absence of selection. Hmmm not quite. Most phenotypic traits, such as neck length in giraffes will display population-level phenotypic variablity and a degree of heritability, generally with a normal distribution around the mean. Under a selection model, reproductive success across the distribution is not even, leading to a shift in the mean in the next generation. Over progressive generations the mean neck length shifts in response to selection. There is no need for a trait to become fixed or even common in a population for it to be selected for - see selective sweep http://www.nature.co...ive-sweep-24827 and population bottleneck http://en.wikipedia....tion_bottleneck . Conceptually, it's an elegant theory, brilliant in its simplicity. Of course the deveopment of novel phenotypes - like feathers is more complex in that multiple mean shifts, interaction between selective parameters and phenotypic characters leading from one state to another, but essentially the same principles apply on a broader scale. As per my previous post - empirically supporting hypotheses suggesting the precise stimuli for uneven reproductive success based on phenotype/environment interaction is difficult. Did a longer neck allow giraffes to exploit a new ecological niche by reaching higher branches? Why don't we see a bimodal distribution of neck lengths? Competition with conspecific species? Was it predator detection? Something we haven't thought of? A combination of multiple environmental factors? Mate choice driven sexual selection? Developing conceptual or experimental frameworks to test independent hypotheses - even with system like giraffe necks we can directly manipulate and observe is very difficult, so trying to do it with now non existent environments and non-emergent traits is functionally impossible - leading to hypotheses being speculative and virtually untestable. Stabilizing selection leads to phenotypic stasis. Another elegant, simple theory I discussed in the first point of my first post in this thread.Giraffe neck length or human heart size are exceptionally poor examples in extremely recently evolved species (H sapiens have been around for ~13 000 generations being generous. Coalescent theory suggests allelic population stability occurs in 4xNe generations. There's no way humans are even close to genetic equilibrium darwin.eeb.uconn.edu/eeb348/lecturenotes/coalescent.pdf). A good example of a trait under stabilizing selection might be something like the functional skull morphology of the crocodilians. It is phenotypically similar across the group and has remained relatively stable since the late Triassic. This suggests that significant modification of this trait has been selectively deleterious under environmental fluctuations for 40 odd million years and thus under strong stabilizing selection. Human hearts and giraffe necks have not been consistent in size or length nearly long enough to infer stabilizing selection. Evolution is continuous process, as random mutation is continuous and the environment is continually in flux. Even the most strongly selectively constrained trait exhibits population level variation, which allows for the action of selective environmental parameters. Species don't simply reach equilibrium and stop evolving. In addition, genes under environmental selection display non-Mendelian models of inheritance and most phenotypic traits are the result of multiple gene interactions. Hrmmm. What you said was : Having "different genetic make ups to start with" is the opposite of sharing a common ancestor. Your statement was pretty concise - now sure how creativity involves interpreting a statement to mean the opposite of what is written. You directly stated that understanding the precise selective driver for the trait of human skull morphology was unknown because our understanding of "genetic evolution" was rudimentary. The reason we can't infer the precise selective driver for ancestral traits is due to our inability to measure the variables and control for each of them, not a lack of knowledge. If those damn physicists could hurry up and make a time machine and a generation speeder upperer to use on our ancestors, we can experimentally test our theories using existing knowledge. In the meantime we rely on model species and systems, extrapolation and inference. Similarly, tectonic theory relies on the extrapolation of observation the suggest the causation of past events, as do many other sciences. Of course, there is more to know about evolutionary theory and empirical proof thereof, otherwise I'd be out of a job but the difficulty in answering the question at hand is due to the above-mentioned practicalities and not a lack of knowledge.

There's plenty of cool examples of parasites that modify host behaviour to suit the parasite: certain fungal infections cause ants to climb to the top of a plant an bite down, assisting the spread of the fungus' pores: http://neurophilosophy.wordpress.com/2006/11/20/brainwashed-by-a-parasite/ Toxoplasma gondii makes mice unafraid of cats, in which it reproduces: http://www.ncbi.nlm.nih.gov/pubmed/11007336?dopt=Abstract rabies makes a host more aggressive, guinea worms create burning pain, which drives hosts to water in which it reproduces, liver flukes in killifish make them less predator weary, nematodes can make grasshoppers jump into water http://www.newscientist.com/article/dn7927-parasites-brainwash-grasshoppers-into-death-dive.html, etc. so the fundamental concept of a parasite modifying host behavior is entirely plausible, though most real world examples are less dramatic than the Hollyowood interpretation.

Ungulates and Primates share a common Eutherian ancestor and thus originate from a common gene pool. The reason they phenotypically differ is not distinct ancestry, but divergent selection and ecological specialization. No one understands "genetic evolution" as the term is nonsensical. Genetic mutation is a component of evolutionary theory and our understanding of it is quite detailed. i.e. - mutational models: http://mbe.oxfordjou.../25/3/568.short http://mbe.oxfordjou.../3/537.abstract http://mbe.oxfordjou...0/2275.abstract - mutation rate estimation: http://mbe.oxfordjou...27/6/1289.short http://mbe.oxfordjou...4/12/2669.short http://sysbio.oxford.../59/2/119.short - phylogenetic reconstruction: http://bioinformatic.../25/7/971.short http://sysbio.oxford.../56/3/504.short http://sysbio.oxford.../56/3/400.short - functional genomics: http://www.sciencema.../5863/620.short http://www.sciencedi...5920/1481.short e.t.c. What is difficult is inferring a precise selective cause for a diversification event. This is an intrinsic difficulty irrespective of the theoretical and empirical knowledge of genetic mutation and the action of selection, as environments are highly complex and dynamic. Even when selective divergence is directly observable (e.g. http://www.sciencema.../5915/737.short http://www.plosgenet...al.pgen.1000929 http://rstb.royalsoc...1506/3071.short) inferring exact causes is excruciatingly difficult as the precise knowledge of environmental conditions, ecological interactions and systemic dynamism are difficult to determine even in systems we can directly observe. Many, many selective pressures act on organisms simultaneously so being able to directly infer a cause and effect event is a formidable challenge in experimental design, information gathering and statistics. Inferring such events in a prehistoric context is functionally impossible and its not through any lack of theoretical understanding. We have extremely well supported theories regarding what sort of events cause selective divergence, how genetic mutation in functional genes manifests and how those two interact, so we can infer broad patterns across extinct taxa and propose broad hypotheses explaining trait selection and divergence. The reason we will be unlikely to determine the exact selective cause of a trait like "intelligence" or "hooves" is that the mind boggling complexity of environmental variables and the similarly complex nature of temporal fluctuations means that the number of plausible explanations is huge, coupled with the practical impossibility of inferring these parameters in long past systems with any degree of accuracy. Not our supposed "rudimentary knowledge."

Unchallengable in that is a truism. It's simply a statement that simultaneous, monotonic growth of all of Earth's biota indefinietly is "unsustainable". While I'm on my soapbox - the concept of sustainability is a bit bollocks IMHO as it's all relevant to a point of reference - the sun's energy is not infinite, so no known life is sustainable given that point of reference. Are you making the implication that humans occupy all ecological niches? This is unequivocally false due to the simple presence of other forms of life demonstrably occupying ecological niches which humans do not. Or that all possible niches are occupied? This would be proven false by ongoing adaptive divergence in a vast number of lineages. Environmental dynamism renders niche space constantly variable. Or that population growth is occurring in all niches? The fact that a large number of species are measurably in decline shows this is not the case. Oscillation of abundance is neither representative of ecological niche expansion, nor an example of infinite growth. This entire example is a non sequitur. Examples of niche expansion include geographic expansion, novel adaptation allowing the exploitation of a new resource and elimination of a competitor. Exponential decay represents another observable model of indefinite population growth. Establishing a logical argument for voluntary human population decline is relatively straightforward if you establish a) that current population levels are above carrying capacity e.g. depletion of renewable resources is higher than replacement rate, e.t.c. and b) there are intrinsic limits to the human ecological niche - e.g. further geographic expansion short of space colonization is implausible, e.t.c. Put simply - If you can establish that we are likely to run out of things to eat and there's no plausible discoveries of enough new things to eat - you have a strong argument for fewer humans. The arguments you're posing here are sweeping generalizations and truisms - posing the politicization of science and abandonment of research which you personally see as counterproductive to your own moral agenda is also not compelling. I sure don't want another political/moralized agenda determining which fields of research are acceptable or not and vehemently oppose the ones that currently exist.

Actually yeah, you do. The evidence suggests that your statements are false. Over a thousand sets of human remains have been repatriated from Britain to Australia, there's no evidence of single compensation claim and the people actively persuing the repatriations claim cultural and spiritual motivations: "Indigenous appeals for the return of their cultural property is fuelled by a strong belief that the spirits of the dead cannot rest until returned to their 'Country', but is also part of a general reassertion of control over their cultural heritage, whether archaeological sites, sacred landscapes or cultural material, and practice in cultural centres and keeping places." http://www.environment.gov.au/soe/2006/publications/emerging/repatriation/index.html Without proof your speculation is dismissible in its entirety, especially in a science forum.

Care to provide any evidence suggesting that compensation has been sought before resting your case on personal speculation?

desal advances - http://www.carnegiecorp.com.au/# Greg - as a biologist, your assumptions are incorrect. Occupation of a new ecological niche, either by geographic expansion, phenotypic or behavioural adaptation can allow for "sustainable" (I hate that word) population growth at a rate of exponential decay. Thus indefinite growth is theoretically possible. The caveat being that if you could prove that human consumption of resource stocks outstrips their replacement and that no new niches are being exploited, you could in turn support the unsustainability of current population levels/growth. The onus would then be on the proponents of growth to suggest where additional resources would come from, as the "we'll think of something" argument is not compelling.

Anecdotal observation of a singular phenotypic trait does not counter the empirical observation of thousands to millions of other traits which statistically support evolutionary theory. Can you propose a hypothesis test by which you can probabilistically support the conclusion that cortical folding in humans, horses and dogs cannot be due to convergent evolution of phenotype? Pot, kettle, etc.

Adaptation of cranial traits can be seen in almost all vertebrates. One of the most reliable, ways to infer adaptation is to measure landmark morphological skull features - often they correlate with diet and environment. There's a few reasons I can think of off the top of my head why enlarged skulls and thus increased analytical intelligence isn't universally selectively advantageous: 1) Enlarging the cranial cavity of a skull comes with several disadvantages. Human skulls are relatively fragile, the area for the attachment of powerful jaw muscles is comparatively reduced, our peripheral vision is reduced my the shape our skulls have taken to allow for a larger brain case, etc. As such, stabilizing selection on a number of other traits can limit the size of the cranial cavity dependent on the ecological niche a vertebrate is exploiting and thus limit optimal size of the brain. 2) Increased intellect in humans is accompanied by a number of other complimentary traits - hands optimized for toolmaking, bipedal locomotion, social structure, etc. which offer positive feedbacks in the evolution of problem solving ability. Other animals do not necessarily have these complimentary features. E.g. say you and a zebra are standing in the grassland together being stalked by a lion - Your intellect alone offers you no selective advantage over the zebra in terms of avoiding predation. Your intellect in combination with other complimentary traits could allow you to buy or create a weapon yourself but given a zebra hasn't got hands, increased ability to think about designing a weapon isn't going to help a zebra avoid said lion. 3) Increased intellect may not even be selected for. If say, speed, or strength is king in the selective environment you are in, taking on the disadvantages a larger, more resource intensive brain costs at the expense of being faster or stronger places you at a selective disadvantage, in turn selection is against increased brain size. For example, sharks and crocodiles are very sucessful predators and both have relatively small brains with relatively limited function. If you look a the skull morphology of both, you'll see they are both extremely specialized - but the selective push is towards bite power and strength, indicating that it is more selectively advantageous for these organisms to be able to bite harder than it is for them to be smarter.

Might pay to educate oneself before making inflammatory false remarks... http://www.creativespirits.info/aboriginalculture/people/aboriginal-remains.html "Aboriginal remains have been removed from graves and burial sites, but also from hospitals, asylums and prisons throughout the 19th century until the late 1940s. Sometimes declared as 'kangaroo bones', they were illegally exported to France, Holland, Scotland, Germany, Sweden, Ireland, England, Austria, the Czech Republic, Italy and the USA". "It is actually on record in the history of Mackay, Queensland, that one overseas collector made a request to the trooper that he shoot a native boy to furnish a complete exhibit of an Australian aboriginal skeleton, skin and skull." —The Sydney Morning Herald, 31 January 1955. "What is also abundantly clear is that there would be no debate at all if the remains were the immediate ancestors of living white Australians." http://dingonet.com/questfor.htm It's estimated that between 1000 and 10 000 aboriginal remains are still in universities, museums, private collections and other institutions in England alone. I wonder how your average Briton would react if these were British remains forcibly exhumed, not released to families or even bodies of people who were potentially murdered so they could be sold to institutions and private collectors for profit... I don't think there's any sensible way to question the ethics regarding the repatriation of indigenous remains or any sensible scientific argument to keep the remains, specifically when no permission to gather them was sought or given, no work has been published using them and UN declarations insist on their repatriation. Though human remains is the most charged issue, the problems with big European museum and university collections withholding materials is much more widespread. In my own experience working on Australian lizards - the initial type sample of the genus I was working on was held in the PMNH. Despite it not having been even looked at since the early 60's, they refused a loan request from Australian museum I was working at. Finally, when a visit was arranged, they were unable to locate the specimen. We requested it declared lost so we could nominate a lectotype and move forward with our research, which was denied. That type should have been repatriated to an Australian institution long ago. Any argument that a big European institution was a more reliable repository for the specimen is rather invalidated by the fact they LOST it. Collective research experience in Australia would suggest it's not an isolated incident - there's a strong argument that all these artifacts, specimens etc would be more useful, relevant and safe back in the nations they were originally removed from. The colonially inspired attitudes of big, European collections is obsolete and obstructionist in a global scientific community.

Overfishing - noted it's not about pollution. The inclusion of those articles was a counter to you suggesting that human activities don't impact on the ocean - overfishing is an example of how human activities have had noticeable global impacts which have in turn, negatively affected the human population. A couple of issues with your suggestion to domesticate fish stocks 1) Domestication is an exception rather than a rule: a very small percentage of species are suitable for human domestication and it is an unsafe bet to assume that domestication of a species is an alternative to wild populations. e.g. replicating the riverine breeding environment required by salmon and the oceanic feeding environment would be extremely challenging and captive breeding of Tuna is proving very difficult e.g. http://scienceline.org/2008/03/env-locke-tuna/ 2) Why domesticate when you can sustainably manage wild stocks? They're free, require no husbandry and provided you exploit them in a sensible fashion, perpetual. As for the deep sea interactions - over 90% of marine organisms live in the "photic zone" or top 200m of the ocean where there is sufficient light for photosynthesis. As such in terms of biotic impacts this is the most important zone for pollution. As for the deep sea, we know less about it than space, so in terms of trophic flows and the importance of the organismal interactions down there, I'm not sure anyone could claim to have robust data. Using the precautionary principle, using it as a dumping ground or ignoring the potential effects of anthropogenic on the abyssal ocean is not a good idea however.

Exactly - there's a more extensive phylogeny on the tree of life webpage I posted earlier. It seems like you're not all that familiar with phylogenetic trees, so I'll explain in basic terms and apologize in advance if it's too simple, but think of the tree in terms of a human genealogy - obviously with a huge number of extinct terminals and unrepresented intermediates. Mammals and reptiles share an ancestor deep in the phylogeny - like a great great great grandfather, but went off on their own branch of the family tree long ago. Turtles are a long lost uncle to the rest of the reptiles. Squamates are the first cousins of the Archosaurs. The lineages within Archosauria - Crocodiles, Sauropods, Therapods, Ornithscians and Pterosaurs are all siblings, the birds of today are the children of the Theropods. In this sense, the Archosaurs, including the birds of today are considerably more closely related to each other than they are to any extant or extinct mammal lineage, and they are a clan nested within the rest of the reptiles. In contrast, the mammals are a group which went on it's own evolutionary way long ago. Not at all. Synapsids - the "mammal like reptiles" evolved into mammals, but not Archosaurs. After this split, the ancestral reptile went through several intermediate stages resulting in many extinct taxa (see tree of life link) and the extant turtles. In the Permian, an Ancestral Saurian - which was uncontroversially a reptile, gave rise to the Archosaurs and the Lepidosaurs. As such, Archosaurs - which contains the dinosaur lineages came along much further down the Retilian lineage than the Syndapsidae and thus bears much more Evolutionary relation to extant reptiles than mammals. Yes. Synapsids evolved into extant mammals, but did not evolve into Archosaurs. Self evident and irrelevant to phylogenetic placement. No. Humans are not monkeys and apes, that is a miscarriage of the Linnaean system of classification. Humans, monkeys and apes are all animals, vertebrates, mammals and primates. Humans and apes are Homonids - sharing a common ancestor, the old world monkeys are not. Old world monkeys are all Cercopithecoids sharing a common ancestor, humans and apes are not. In the same sense, Mammals and reptiles and birds are all Amniotes, sharing a common ancestor. the Archosaurs and the extant Squamates are also in the subclades Reptilia, Diapsidae and Suaria, indicating a much longer period of common ancestry between extant reptiles and Archosaurs than between the mammals and the Archosaurs. Well unless you reject the entire system of Linnaean classification, by common ancestry, crocodiles are a linneage within Reptilia, sharing a common ancestor with the rest of the Reptiles and are therefore classified as reptiles. Convergent evolution may make classification difficult in some cases, but what we generally base classification on is common evolutionary history. Phenotypic divergence is irrelevant. Komodo dragons and crocodiles share more common ancestry than either do with lions, ergo crocodiles and komodo dragons are reptiles, lions are mammals. Dinosaurs shared more common ancestry with reptiles than they did with mammals and are similarly, considered to be reptiles.

You could investigate mtDNA mispriming via a blast search or if an mtDNA genome exists for your study species, an alignment to it - edit you already tried it, sorry. Errors in scoring could also be possible if you're using an algorithm and there's preferential fluorescence of one nucleotide over the other allele. Otherwise I'd investigate the possibility of selection and remove the locus from all analyses assuming HWE. If there's a geographic pattern to it you could be looking at a "genomic speciation island" or similar.

Not perhaps because they are written for an audience with an assumed level of knowledge and therefore expected to use technically correct terms? Scientific articles are intended to add to the body of knowledge. They have a word limit. They assume the reader is scientifically literate and knowledgeable about the current state of the field. They therefore use technical terms to convey information and are densely written. If I review a paper and the author has used a whole sentence to explain something where a single term would suffice and be more technically correct, I edit it - e.g. "parapatric" rather than "the geographic distributions of the two entities had a partial area of overlap." Its more concise, more technically correct and the intended audience will know what it means. I used the Deep Horizon example too. I'm pretty sure 5000 feet below the surface of the ocean counts as not "on, or close to, the surface of the sea". Again, the fact we can observe detrimental effects of anthropogenic activities on a global scale renders this statement false. I posted some scientific articles previously but here's some popular literature: http://www.nytimes.c...nce/03fish.html http://www.newscient...e-collapse.html http://ocean.nationa...rine-pollution/

You state: Which is clearly proven false by the phylogenetic placement. Dinosaurs are much more reptiles than mammals are reptiles. Synapsidae - the ancestral mammalian lineage is a monophyletic, evolutionarily independent lineage basal to extant Reptilia. Archosauria - which contains the crocodiles, birds and dinosaurs is nested within extant Reptilian lineages and is thus, phylogenetically speaking, much more closely allied with extant reptiles than it is with extant mammals. You then counter with a suggestion of an alternative phylogeny: I'm wondering what you would base an alternative phylogeny on in the face of the bulk of scientific evidence supporting the arrangement in the figure I posted: http://www.tandfonline.com/doi/abs/10.1080/02724634.1991.10011426 http://www.sciencemag.org/content/283/5404/998.short http://jpaleontol.geoscienceworld.org/cgi/content/abstract/75/6/1185 http://www.jstor.org/stable/4523513 http://onlinelibrary.wiley.com/doi/10.1111/j.1475-4983.2009.00918.x/full etc ad infinitum. All reconstructions of the vertebrate phylogenetic tree of life place Synadspids as basal to Reptilia and Archosaurs as well and truly nested within. The crudeness of the diagram comes from the lack of nodal support values and branch length scaling, not the placement of lineages. This is a false dichotomy. Aves and Squamata are reciprocally monophyletic as are Crocodilia and Squamata. Archosauria IS NESTED WITHIN REPTILIA. It's like saying "Ostriches are no more birds than parrots or robins are hawks."

Do you generally read peer reviewed papers? If so, how are these different in terms of writing style from the ones you read elsewhere? Say you have a party, 50 people come. They all track mud on your carpet. You tell one of your guests you're annoyed about it. He gets huffy and says "Show me exactly where I dirtied your carpet, then." It's a false proposition because each contribution is cumulative and disperses over time. Unless he just walked in, you'll be unable to find his precise footsteps whether or not he tracked mud in or not. Given we know that the pollutants on those WWII vessels have a demonstrable effect on oceanic environments, it is logical to assume that they did. Examples of catastrophic releases of oil like the Exxon Valdez, Deep Horizon, e.t.c, and the immediate effects they have on the marine environment are in abundance. However as these effects were not measured during WWII, no one will be able to furnish you with facts and figures when they weren't recorded and a lot of other pollution has occurred since.

Quite simply, no. This assumption was never made. The phylogenetic placement shows this is simply not true. Look at the tree - Dimetrodon was a basal Synapsid. Crocodilians and dinosaurs are Archosaurs. As such, Crocodiles are considerably more closely related to dinosaurs than Synapsids. You'd need a radically different phylogeny to support your statement. Synapsids are again, not Archosaurs and relatively distantly related to Archosaurs in comparison to extant reptile taxa. It seems you might be making an error in assuming that the basal Synapsidae are Archosaurs (dinosaurs) which they are not. If organismal evolution hadn't progressed the way it happened to progress the entire biota of the planet would by definition, be distinct from what is observed today. Determining which lineages would and wouldn't have succeeded given a hypothetical change in historical events is ludicrously speculatory. Yes. Aves - a phylogenetically reptilian lineage has feathers. Under a biological species concept, the generally accepted vertebrate species concept since Mayr 1942, birds would rightfully be reptiles. The caveat I've now mentioned three times No one ever stated that Synapsidae did not share a common ancestor with Reptilia - the argument is a straw man. The issue is that Archosaurs are nested within modern Reptilian lineages, Synapsidae are basal to all of the modern reptile lineages. There's simply no way to argue that the dinosaurs could share more affinities with mammals than reptiles, unless you reject the phylogeny altogether, in which case you'd need evidence of an alternative scenario which outweighs the evidence supporting the current one.

While any scientific conclusion acknowledges that it may be incorrect, that "crude" phylogeny is supported by a large body of scientific evidence. I chose the image because of its simplicity and relatively low level of assumed knowledge. Blow up Diapsida: There's the Archosaurs! a well and truly derived group within Reptilia (along with Aves, the aforementioned caveat). http://tolweb.org/tr...ial_Vertebrates is a more complete summation of the current phylogenetic understanding of the group. In addition almost all studies show that the split between Mammalia and Reptilia is basal in relation to the internal split between the Archosaurs and the rest of Reptilia, so this: is also in contradiction to current best knowledge. So in summary my point was: phylogenetically speaking - the dinosaurs are considered reptiles, they arose considerably after the Mammalia did and none of the organisms one would classically or technically consider to be dinosaurs bear closer affinities to mammals than reptiles.

The phylogenetic placement disputes this: Archosaurs are indeed reptiles by phylogenetic placement. And this: Pterosaurs, and theropods and sauropods - your classic dinosaur taxa are nested within extant reptile lineages and thus have much closer affinities to reptiles than mammals. Other extinct animals indeed bear closer relation to mammals, but these aren't typically considered dinosaurs. The caveat of course is that phylogenetically, birds are reptiles too. In hindsight I should have quoted the more relevant portions of your post.

An absence of heterozygotes indicates deviation from Hardy Weinberg equilibrium. What is the locus and could it be under selection?

Phylogenetic analysis disagrees - the dinosaur lineages are nested within extant reptile lineages and as such did not give rise to mammalian taxa. e.g. with one caveat

It goes to clarity and effort - there's no real excuse except laziness for using "txt speak" when you have no word limit and a full qwerty keyboard at your disposal. Further, it's a lot harder to understand a post with misspelled words and no punctuation than a post with basic sentence structure. So basically you're asking others to go to extra effort to understand your content because you're too lazy to write properly. As for the initial question - death is the inevitable terminus to life. Everything and everyone dies in a process fundamental to the perpetuation of life on the planet. No one likes the idea of not existing anymore, but when you actually contemplate the idea of immortality given the way life on earth exists and evolves, it's not particularly appealing either. That said, I'd rather check out peacefully in my sleep after a long, fulfilling existence, so maybe the "prevention of premature and painful death" is a better goal?

Biological systems recover from extinction events, sure. Only it occurs over geological time scales and the system does not identically replicate the previous in function or form. Using the purely utilitarian argument, as a species we don't have the luxury of waiting for systems providing us with critical services that we disturb to return to equilibrium before we either go extinct or find an alternative. Given we have these systems which support our existence by providing suitable breathing air, food, clean water, climactic conditions conducive to human civilization that need us to do nothing and are effectively free. Disrupting them through introductions and the removal of species demonstratively reduces their ability to provide those services to us. As such, it is in our best interests to conserve them in their most biodiverse and thus the state in which they are most efficient and resilient to environmental fluctuations.

As has been covered earlier in the thread. Functioning ecosystems provide services fundamentally crucial to human life. Ecosystem function is reliant on an as yet, poorly documented diversity of organisms and maximized diversity makes these systems resilient to environmental fluctuations. As a result, if a human induced species introduction reduces the biodiversity and therefore function of an ecosystem, as is usually the case with introduced species, it is in our utilitarian best interest to prevent that reduction in diversity and function. There is no need to invoke any ethical or moral argument to strongly support concept of anthropogenic causes of species extinction being disadvantageous - and that doesn't discount ethical and moral arguments either.