Industrial Deals Best Books of the Month Amazon Fashion Learn more nav_sap_plcc_ascpsc $5 Albums Fire TV Stick Sun Care Handmade school supplies Shop-by-Room Amazon Cash Back Offer CafeSociety CafeSociety CafeSociety  Amazon Echo  Echo Dot  Amazon Tap  Echo Dot  Amazon Tap  Amazon Echo Starting at $49.99 All-New Kindle Oasis AutoRip in CDs & Vinyl Segway miniPro
Customer Discussions > Science forum

Are there SCIENTIFIC disagreements with evolution theory?


Sort: Oldest first | Newest first
Showing 101-125 of 860 posts in this discussion
In reply to an earlier post on Oct 4, 2012 12:45:55 PM PDT
Jason: forums or fora?

Depends whether you're speaking English or Latin.

Posted on Oct 4, 2012 1:15:53 PM PDT
Re: forum versus fora. I have credentials as well. It's a word going through transistion because of the increased use of forums/fora. I used to always say fora, then decided on internet forums in which I was using contractions and slang, forums would be more appropriate than fora. I just now use whatever hits me at the time. No one is right or wrong for using either.

OTOH, using the Roman plural for something like forum, a place central to Classical Rome, may seem more appropriate. OYAH, magnitudes more people now use electronic forums than ever used Roman fora.

Do what you amuses you. Don't even have to be consistent.

In reply to an earlier post on Oct 4, 2012 4:16:19 PM PDT
Doctor Who says:
Yes, these threads do exist. They also happen do end more quickly since there is only so much to say on a particular subject. Some of these turn into long battles if a creationist or similar decides to take offence.

In reply to an earlier post on Oct 4, 2012 6:42:34 PM PDT
Deleted my previous post which seemed to have offended the superior beings on the forums.

In reply to an earlier post on Oct 4, 2012 7:00:59 PM PDT
Jason: forums or fora?

I work with so many people that do not speak or write competently that I often go hard over the other way, hence 'fora'. "Forums" is almost as bad as when someone tries to formally address a group of men as "sirs" rather than the correct collective; 'gentlemen'. On the other hand, I haven't criticized other peoples grammar or word choices on this forum, and it is no skin off my rear end if someone chooses to write in the vernacular.

But I digress.

No, there are no *scientific* disagreements with evolution theory. Lots of theological ones, though.

In reply to an earlier post on Oct 4, 2012 10:55:29 PM PDT
Re Van Court, above: As a collective, "sirs" has made its way into the language, and "gentlemen" has largely become obsolete as an introduction to letters. (It remains, of course, as part of "Ladies and gentlemen".) Once upon a time, "messieurs" was used; traces of this remain in "mister".

In reply to an earlier post on Oct 4, 2012 10:58:13 PM PDT
Barbaric decadence, isn't it?

But far more relevance is the barbarism of people who refute science to embrace ignorance.

In reply to an earlier post on Oct 4, 2012 11:20:23 PM PDT
Last edited by the author on Oct 4, 2012 11:22:34 PM PDT
Sceptic says:
Darwinian medicine is in its infancy. There are many evolutionary hypotheses in medicine these days. They are work in progress; not dogma.
2.1.2 Evolution: medicine's most basic science
Randolph M. Nesse and Richard Dawkins
Nesse, R. M., & Dawkins, R. (2010). Evolution: Medicine's most basic science.
In D. A. Warrell, T. M. Cox, J. D. Firth & E. J. J. Benz (Eds.),
Oxford Textbook of Medicine, 5th edition (pp. 12-15).
Oxford: Oxford University Press.
The role of evolutionary biology as a basic science for medicine has been expanding rapidly. Some evolutionary methods are already widely applied in medicine, such as population genetics and methods
for analysing phylogenetic trees. Newer applications come from
seeking evolutionary as well as proximate explanations for disease.Traditional medical research has been restricted to proximate studies of the body's mechanism. However, separate evolutionary
explanations are also needed for why natural selection has left many aspects of the body vulnerable to disease. There are six main possibilities:
mismatch, infection, constraints, trade-offs, reproduction at
the cost of health, and adaptive defences.
Like other basic sciences, evolutionary biology has limited direct clinical implications, but
it provides essential research methods, it encourages asking new questions that foster a deeper understanding of disease, and it provides a framework that organizes the facts of medicine. Physicians
who understand evolution recognize that bodies are not designed machines, but jury-rigged products of millions of years of natural selection that work remarkably well, given that no trait can be
perfect, and that selection maximizes reproduction, not health.

In reply to an earlier post on Oct 5, 2012 8:00:59 AM PDT
Dr. Paul S. J. Smith: You say regarding why we are vulnerable to disease: "There are six main possibilities: mismatch, infection, constraints, trade-offs, reproduction at the cost of health, and adaptive defences." Do you believe that the vulnerability to age-dependent diseases could be the result of a suicide mechanism that evolved because a limited life span conveys some sort of evolutionary advantage, i.e. "programmed aging? This based on the idea that some "wider" non-reproductive benefit of a limited life span can trade-off against the reproductive disadvantage of a limited life span. If so, why. If not, why not.
"Constraints", and "infection" as an explanation for age-dependent disease seem to be incompatible with the observation that different mammals have grossly different life spans but presumably similar exposure to infections and presumably similar constraints.

In reply to an earlier post on Oct 5, 2012 8:59:28 AM PDT
Re Frango, above: It isn't a suicide mechanism per se -- it is the fact that long life requires resources (see below) and doesn't necessarily contribute to reproductive success. Therefore, there is no particular evolutionary pressure for longevity.

Generally, chromosomes lose one codon at the end during replication, which limit the total number of replications possible. There are two ways of dealing with this:
- Extra placeholder codons at the end of the chromosome, of which one can be lost at each reproduction without affecting the active genes. The typical human chromosome has on the order of 40 of these.
- A special mechanism for gametes which preserves the extra codons, so that they can be passed to the next generation unaltered. Look up "telomerase" for more on this.

In reply to an earlier post on Oct 5, 2012 9:02:50 AM PDT
M. Helsdon says:
""Constraints", and "infection" as an explanation for age-dependent disease seem to be incompatible with the observation that different mammals have grossly different life spans but presumably similar exposure to infections and presumably similar constraints."

The 'heartbeat hypothesis' points to a close correlation in mammals (and others) between the number of heartbests/breaths, and lifespan. A lowered heartbeat or lower metabolism tends to correlate with a long lifespan, suggesting that there's a point where the body simply wears out (whilst mechanisms exist to remove some waste products others just accumulate to a point where malfunctions or reduced or no function occurs), and prior to that point becomes increasingly prone to disease due to the decline of the immune system, and increasing cell replication errors.

In reply to an earlier post on Oct 5, 2012 10:00:52 AM PDT
Last edited by the author on Oct 5, 2012 10:06:08 AM PDT
Sceptic says:
Hi There are a lot of questions in there.
I would suggest you read Randolph Nesse's book" Why we get sick" as an introduction to the field.
I do not really"Believe" anything dogmatically. Rather I accept the best hypothesis that explains the data,going. That can change with new experiments and data.
After reproductive years Natural selection pressures take a back seat which is why we are all dead at 130 years old. Different selective pressures act at different stages.

In reply to an earlier post on Oct 5, 2012 10:03:27 AM PDT
Sceptic says:
When individuals in a population vary in ways that influence their genetic contribution to future populations, the average characteristics of the population will change. This is not a theory; it is necessarily true. Natural selection involves no design, no planning, and no goal. The word `evolution' refers more generally to any changes over time in a population, whether from selection, mutation,
genetic drift, or migration. Notwithstanding his most famous title, Darwin's greatest contribution was not his explanation of speciation, but his explanation of adaptation. Recent research on the Galapagos finches known as `Darwin's finches' illustrates the point. During drought, only larger seeds are available, so individuals with larger beaks get more food and have more offspring. In just a few generations, the average beak in the population became significantly larger after a drought. When the rains came, and small seeds again became plentiful, selection switched to favouring smaller beaks. No trait is adaptive
except in relation to a specific environment.

In reply to an earlier post on Oct 5, 2012 10:05:03 AM PDT
Sceptic says:
For instance, one might expect pathogens to evolve low virulence: killing off the host is surely not good for the group! However, even long association of a host and pathogen does not necessarily
decrease virulence. People who are out of bed transmit a rhinovirus faster; this selects for low virulence. The story is very different for insect-borne diseases. Plasmodium is transmitted faster from
patients who are too sick to slap mosquitoes, so virulence is high for malaria in humans (infected mosquitoes feel just fine). Ageing can be similarly misunderstood. One might think that
senescence could speed the evolution of the species by making room for new individuals. The species, however, is not the level at which selection acts. Consider a lethal or deleterious gene that is expressed
only late in life. Many carriers will have passed on the gene before it kills them. The same gene would be quickly selected out if it killed individuals before they reproduced. We are all descended from
individuals who died after having children. Not one of our ancestors ever died in childhood! Moreover, a pleiotropic gene that gives a benefit early in life may be favoured, even if it causes deleterious
effects later, when selection is weaker. This evolutionary explanation for senescence is now confronting remarkable new evidence that single-gene effects in the insulin signalling pathways can have
huge effects. The reasons why selection has not incorporated such changes will prove most interesting.

In reply to an earlier post on Oct 5, 2012 10:07:45 AM PDT
Sceptic says:
Mismatch
Chronic `diseases of civilization' such as obesity, hypertension, and diabetes are now pandemic. The motivations that make us eat too much and exercise too little were shaped for an environment where
sweet, fatty, or salty foods were good for us, and excess exercise could be fatal. Recognizing the origins of our unhealthy preferences does not change them, but it illuminates the source of the problem and possible solutions. Similarly, allergies and autoimmune disorders are more common in developed societies. Our immune systems evolved when people were routinely exposed to intestinal parasites and pathogens. In their absence, inhibitory immune cells are not stimulated, leaving the system overactive and responsive to self.

In reply to an earlier post on Oct 5, 2012 10:09:40 AM PDT
Sceptic says:
A related point explains the differences in mortality between the sexes. A trait that increases reproduction will tend to spread, even if it harms health. Investments in competitive ability give greater
reproductive pay-offs for males than for females, so men have been shaped to take more risks and to invest less in bodily repair. Data from developed societies shows that mortality rates for men at the
age of sexual maturity are about three times higher than that for women.

In reply to an earlier post on Oct 5, 2012 10:26:40 AM PDT
Roeselare says:
If multicellular life evolved fixed lifespans to speed up adaptation, the contemporary organisms that never evolved this survival advantage apparently died out.

Similarity in the number of lifespan heartbeats among non-hibernating homeothermic animals.
Livingstone SD, Kuehn LA.
Abstract
An investigation was made of the available data on heart rates and maximum lifespan of a number of vertebrates from a variety of sources; only data pertinent to resting adult non-anesthesized homeothermic mammals and birds in a state of thermal neutrality were subsequently analyzed. All known hibernators were excluded because of their extreme, and largely unknown, range of heartbeat from season to season. Plots of heart rate (beats per minute) against reciprocal of lifespan in years showed surprisingly good fits (r = +0.90 for mammals and r = +0.64 for birds). Computation of the total number of heartbeats in the maximum recorded lifespans of the mammalian and avian species involved in this study showed that the mean cumulative heartbeat number for 31 mammalian species was 100 +/- 8 S.E.M. x 10(7) beats and for 23 avian species was 326 +/- 22 S.E.M. x 10(7) beats. This paper documents this analysis, which supports the concept of a close similarity in lifespan heartbeats among mammalian species and among avian species.

In reply to an earlier post on Oct 5, 2012 10:41:33 AM PDT
Last edited by the author on Oct 5, 2012 10:42:56 AM PDT
M. Helsdon says:
"Chronic `diseases of civilization' such as obesity, hypertension, and diabetes are now pandemic. The motivations that make us eat too much and exercise too little were shaped for an environment where sweet, fatty, or salty foods were good for us, and excess exercise could be fatal."

Given that for the majority of humanity, civilisation, as in living in complex large societies, is a recent occurence, and a tiny percentage of the history of our species, its effects on the species are limited, if not for the individuals who unintentionally shorten their lifespan by 'life choices'. For that matter, the modern risks of civilisation ("obesity, hypertension, and diabetes") are nothing compared with the less recent effects of living in complex societies. Until comparitively recently, cities consumed most of the people who lived within them resulting in severely shortened lifespans due to sanitation and the ease with which disease could be 'shared'.

In reply to an earlier post on Oct 6, 2012 2:12:57 PM PDT
Robert A. Saunders:
Re telomeres: I have never understood how simple telomere shortening can explain how some types of cells that divide very rapidly (such as epithelial cells) would not fail in a very short time if all cells have the same telomere shortening problem. If cell types differ, then there must be an overriding supervisory function determining when to supply telomerase or otherwise control the deteriorative process. Likewise, if similar species have very different life spans, it would seem to require differences in the supervisory function. This idea is not incompatible with a suicide mechanism acting to supervise the deteriorative process, in this case, telomere shortening.
It is not clear to me how "long life requires resources"? Would an older animal somehow need more resources than a younger one?
The "suicide mechanism" concept is based on various observations of complex mechanisms that cause deterioration such as genes that cause aging. If it is a complex mechanism can we presume that it has evolved for some purpose? The suicide concept is also supported by various evolutionary theories to the effect that a life span longer that some amount creates an evolutionary disadvantage, thus encouraging the evolution of a suicide mechanism.

In reply to an earlier post on Oct 6, 2012 2:14:25 PM PDT
M. Helsdon:
Heartbeat hypothesis seems to be incompatible with many observations:
Does an elephant really have the same heart/respiration rate as a human although similar life spans? Does a parrot have a six times slower heart rate as a crow (maybe, I don't know). Why would waste accumulate 90 times faster in a mouse as human? Is a mouse metabolism really 90 times faster? Why do small dogs live longer than big dogs?

In reply to an earlier post on Oct 6, 2012 2:16:27 PM PDT
Dr. Paul S. J. Smith:

Yes, "after reproductive years" end, there is clearly drastically reduced evolutionary need for longer life span. Also, I agree that there can be trade-offs between reproduction and survival. But why do "reproductive years" end? For virtually any species, one can find some other similar species that reproduces longer. Some species apparently do not age and apparently do not suffer from reproductive deterioration as their age increases.

New evolutionary ideas say that there can be an evolutionary disadvantage to reproducing longer than some age that varies from species to species as well as a disadvantage to surviving longer. Consequently organisms evolved mechanisms for limiting survival and reproduction. This idea seems to fit a lot of observations.

In reply to an earlier post on Oct 6, 2012 2:44:21 PM PDT
"Why do small dogs live longer than big dogs? "

This is an artifact of domestication. All dogs mature at the same rate (whether a chihuahua or a Great Dane, puppies are ready to leave their mother at around 6 weeks). Thus dogs who have been bred to be large have a speeded development compared to the medium-sized dog morphotype, vice versa for small dogs. Large dogs burn out fast and small dogs burn for longer.

In reply to an earlier post on Oct 6, 2012 2:47:29 PM PDT
Last edited by the author on Oct 6, 2012 2:49:55 PM PDT
[Customers don't think this post adds to the discussion. Show post anyway. Show all unhelpful posts.]

In reply to an earlier post on Oct 6, 2012 3:09:14 PM PDT
M. Helsdon says:
"Does an elephant really have the same heart/respiration rate as a human although similar life spans?"

No, it has a heart beat about half as fast, but elephants have a higher blood pressure than humans. African elephants in the wild can reach fifty six years.

Note I said a 'close correlation', not an exact one.

"Does a parrot have a six times slower heart rate as a crow"

A crow has a heart beat above three hundred and fifty, a parrot of about two hundred. In captivity a crow can live for thirty years, a parrot, depending on species, around sixty.

"Is a mouse metabolism really 90 times faster?"

A mouse heartbeat is around five hundred, a human, seventy. A mouse can live a year and a half in captivity. A human lifespan today varies, by nation between averages of thirty two to eighty two.

In reply to an earlier post on Oct 6, 2012 5:29:17 PM PDT
CFM

We know however that 'the fallacy of combined, bilateral, extrinsically redundant polyperverse fallaciousness' when properly defined, makes a very bad Mary Poppins song.
[Add comment]
Add your own message to the discussion
To insert a product link use the format: [[ASIN:ASIN product-title]] (What's this?)
Prompts for sign-in
 


Recent discussions in the Science forum

 

This discussion

Discussion in:  Science forum
Participants:  53
Total posts:  860
Initial post:  Sep 28, 2012
Latest post:  Oct 19, 2013

New! Receive e-mail when new posts are made.
Tracked by 3 customers

Search Customer Discussions