Is evolution a continuous process?

Question

Is evolution, as Darwin describes it, a continuous process?
What are your evidences for your views on the topic? Can we expect a big turn in the characteristics of various species in the future? If yes, what could influence this change?

What elements in our modern world may affect the next generation of humans (or other species)? What can be the manifestations of evolution in our modern world?

Answer 1

Evolution is a continuous process. The speed and direction of evolution in a particular form may be different from others.
Macroevolution and microevolution have different characteristics.The prime source of evolution is mutation. Natural selection provides the adaptive channel and imparts directionality.

Answer 2

>>Is evolution, as Darwin describes it, a continuous process?

As Darwin described it...not quite. As we know evolution now...absolutely. Evolution entails a build up of mutations that occurs over long periods of time affected by the natural environment. If one of these processes isn't occurring, the other most assuredly is.

>>What are your evidences for your views on the topic?

There are numerous papers that show build up of mutations in different species, and quite a few that document speciation due to natural selection. If you want a few examples, email me.

>>Can we expect a big turn in the characteristics of various species in the future?

I'm not sure what you mean by "a big turn"...what constitutes a big turn? And which species? It's probably likely that at least one (if not a few, if not many) species will develop new characteristics, especially if the rate of environment change continues at the pace it is theorized now.

One of the problems with predictions is the number of factors that are involved in causing the prediction to come true. The more factors involved, the less likely someone is to be correct about the prediction. And evolution is an extremely complex process with numerous factors involed, both within and outside the organism/populaiton. Making predictions of the nature of when an organism will show significant changes or even become a new species is an extremely difficult proposition. I know this is something of a cop-out on the answer, but it's true.

>>If yes, what could influence this change? What elements in our modern world may affect the next generation of humans (or other species)?

Again, there could be numerous elements. The proliferation of human technology is the most likely candidate (in my mind). Not only is it causing dramatic environmental changes, but it also breaks up and disturbs the equilibrium of many ecosystems.

>>What can be the manifestations of evolution in our modern world?

In my mind, the most likely manifestation will be the loss of specialized species in favor of more generalists. It's an extension of the theory of evolution that a generalist species (a species that can utilize various parts of environment for food, water, living space, etc.) is more adaptable to environmental changes, and therefore more likely to survive than specialist species (those species that can utilize only one of very specific parts of the environment for food, space, water, etc.).

Answer 3

Evolution is the term used to describe changes to a species over time. This definition presupposes that this is a continuing process.

Can we expect a big turn in the characteristics of various species in the future? That depends on a number of factors. What is your timeline? If it's only one generation, probably not. If your timeline involves thousands of generations, probably so.

What changes will occur in the environment? Will these changes be gradual ( such as a build up of pollutants in our atmosphere) or sudden (such as the Earth being struck by a large meteor, or some lunatic detonating a nuclear device)?

What elements in our modern world may affect the next generation of humans (or other species)? The previous paragraph suggests some of these elements.

One thing that has not been addressed by prior answerers --- survival of the fittest. The other answers are presented as if an environmental change occurs, so the species adapts. No, this is not the case. Yes, a change occurs --- a natural disaster, a disease, gradual build up of pollutants. Those who survive due to strength, disguise, natural immunity or mental acuity are able to reproduce (have children). The characteristics that enabled them to survive are passed to the progeny that also survive and reproduce.

What can be the manifestations of evolution in our modern world? Nearsightedness is an example. In the early days of humans, most people were farsighted. Farsighted people were able to prepare for a predator better than nearsighted people because they would see the predator sooner and have more time to prepare. Most people were farsighted because nearsighted people were killed by predators and unable to reproduce. In our modern world, variations in vision are corrected with glasses, contact lenses and surgery. Nearsightedness and farsightedness no longer determine survival and ability to reproduce. Therefore, in modern society, nearsightedness is much more common.

Answer 4

> Is evolution a continuous process?
Not per se. In organisms which are well adapted to their environments, and with the environments not changing, the organism may not have a change in phenotype for very long periods of time. The classic example of this is Triops cancriformis, the modern version of which appears to be identical to a species extant in the Mesozoic era.

You should google around for "punctuated equilibrium" to get a better description -- if there aren't external selection pressures, then populations may not change over long periods.

> Can we expect a big turn in the characteristics of various species in the future? If yes, what could influence this change?
The populations which are best able to co-exist with mankind will be the ones that flourish.

> What elements in our modern world may affect the next generation of humans (or other species)?
In humans, it's the choice to have children. Women with educations and careers have fewer children than those who don't. You can speculate that in the future, girls will be less interested in having educations and careers. This might be a decrease in the average intelligence of the human species.

Answer 5

It is important to understand what the word "continuous," implies. It has, in fact, a very defined mathematical meaning. In differential topology, you can create a continuous surface that appears to be a jump in lower dimensions. The jump occurs outside our view.

The popular culture example is a "tipping point," or the "straw that broke the camels back," but what it says is that you can have a continuous process that you cannot observe and so will appear as jumps.

To apply this to evolution consider the simple case of a mutation. Imagine humans have a specific set of codons that are always the same. If one child has a variation, that variation may pass through to their children. This transmission of course is unseen. It may be irrelevant, however when combined with a specific set of other genes in subsequent generations or when other mutations occur, a large outward physical manifestation may appear to have occurred, when in fact, it was not large, but many small but unobserved changes.

Now, because this is a "discrete" and not a "continuous" process, jumps are more likely. It is rather like not being able to purchase something for 1/7th of a dollar. You have to round and rounding introduces error into the system permanently and those errors may be impossible to remove from the system.

We cannot predict the future. Yellowstone's Caldera could erupt killing almost all human life. People who lived in particular niches or who were somewhat immune from the cold would bear particular advantages. Who they are and what that means is something we cannot know now. Likewise the ozone layer may collapse and who knows what may happen, or how global warming will impact survival.

Scientists are in fact tracking gene changes as they occur now by sampling global populations and watching differences propogate through the species.

Answer 6

Yes, it is a continuous process. While Darwin was off on somethings he was spot on in the most significant areas.
I try to point to the human body though most think I take this too far.
I point to things like Wisdom teeth- people are being born without them at a graduating rate (we've no need for them.)
Appendix's - same scenario, they're disappearing.
I think in the next two hunred years or so human beings will no longer have hair on their bodies.
The truth is that we have started to evolve sociologically which includes adapting in that way, not by physical changed. So, instead of growing more hair beacuse we're cold, we build jackets and such- after hundreds of years I believe hair will no longer be a part of our physical make up.
Most people say that we won't be sexy and such and who would be attractive? The truth in the answer to that question also lies within history- sexual visions change, as they always have and they always will to continue the propagation of the species...
You do realize at some point in the 60-70's human beings had to think hairy smelly greasy horribly unhygienic hippies were sexy!

Answer 7

If you are sitting there waiting for one of the higher animals to suddenly disappear and reappear as a new species, you are wasting a lot of time. Same goes for a change is characteristic.

Obviously evolution is continuous. Fossil evidence shows that. But, there have been major shifts, brought on by major changes, like asteroid inpacts.

What has influences changes in the past? Dinosaurs die off due to a cataclysmic event that racked the whole of Earth. Millions of years later, mammals being to appear. So, out of the muck and rubble news species evolve.

You will never witness evolution. The next asteroid that slams in to Earth will more than likely kill a significant number of humans. Perhaps events post will see the eradication of Homo spp. Perhaps a different hominid will arise from the ashes. But it wont be in 70 years, nor 1000, maybe a million.

We humans have the ability now to shape our own genetic future. Therefore human evolution is now in the hands of humans. I don't think it is gonna be pretty.

I think the greatest hindurances to people trying to understand evolution is the time scale. We humans are generational animals. We know our parents and grand parents, children and grand children. Therefore humans are lock in to a very narrow time span. We live 70 years, we see people older and younger, by about that same number of years. So it is difficult to get a handel on events beyond that span. Most people cant get a grasp on 1000 years. That's 15 human generations. How could they possibly comprehen 1000000 years.

There was an excellent paper written by N. J. Matzke, Evolution in (Brownian) space: a model for the origin of the bacterial flagellum. http://www.talkdesign.org/faqs/flagellum.html. Try to read it. It is complicated, something I am sure the Creationist will not tolerate. If it aint simple it aint worth the time. Yes, from simple minds come simple answers.

Ther has been completed excellent work on how bacteria evolve.
Bacterial Evolution/Adaptation and Antibiotic Resistance
http://www.lsic.ucla.edu/classes/mimg/robinson/micro12/m12webnotes/Emerginginfections/m12bacterialevolution.htm

If you wanna understand evolution on a more user friendly time scale, try reading the following.
Origin and Evolution of Influenza Virus Hemagglutinin Genes
http://mbe.oxfordjournals.org/cgi/content/full/19/4/501

Indeed there are reams and volumes and tons of data, records, cold hard facts, bones, fossils, skeletons, amber blocks, ice cores, etc etc etc. That fully support the changes over time we refer to as evolution. Perhaps it is just too much for some people to comprehen.

Answer 8

There are so many variables in the time-line of any species that this question becomes almost impossible to answer. Evolution is a continuous process but the environment can suddenly change and precipitate a sudden jump in evolution. To say that evolution is only a slow process or only comprised of occasional jumps is a narrow view. Evolution is the result of natural selection and so if you recognize natural selection and understand it then you understand the essence of evolution and believe in it.

Answer 9

Yes its continuous. Every reproduction is a small change in the genetic information of the species, over long periods of time, with environmetal factors selecting which is more likely to reproduce, you get evolution.
I do expect a lot of changes with most of the species on earth. Humans have had a large affect on the planet in the past several hundred years; other organisms are going to need to adapt.
It seems that in todays society, intelligent people end up spending more time at college and more time being involved with work and have less time for children. Therefore there are less genes for intelligence being passed on over all. After a few more generations of this, I'm a bit worried of the outcome. Smart people need to start breeding!

Answer 10

Evolution is all about self-maintenance program for the survival of a species. It's slow because it depends on transitions in DNA between generations. One is good DNA preserved because it had a chance to get with it, the other is random mutations in DNA. Sometimes no changes can happen because the evolution process encounters a minimum or local minimum. (A ball getting stuck in crater midway downhill)

I think we will see healthcare costs continue to grow as a consequence of our technology reprieving evolutionary mechanisms. AIDS is a good example. (Not saying either is right or wrong) You can either spend a bunch of money to cure and prevent a disease or you can let everyone with AIDS die hoping that spreading rate is less than death rate. But apply to any other potentially genetic or culturally hereditary disease.