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1

Indeed natural selection decrease variability and therefore decrease information and mutation recreate this information. You can think of a bunch of pens of different colors. If you select for the red pens you will decrease the variability in pen colors as the other colors will slowly disappear. If you allow for mutation to occur you will recreate blue and ...


0

Was it necessary for the common ancestor with fused chromosome 2 to mate with another creature whose 2 chromosomes fused in a similar manner? Of course not. People with balanced translocations have kids with people with the wild-type chromosome arrangement all the time. Such people have some fertility problems, due to problematic meiosis leading ...


5

Several issues here that make your question unanswerable: Intelligence is not defined. How would you define it? What kind of relationship are you exactly looking for? Comparing average intelligence between groups or trying to fit a regression with intelligence on the Y-axis and relatedness to human on the X-axis? The general issue hidden behind methods of ...


1

Could not fit in a comment… What kind of observations will you accept to be an observation? If we can demonstrate showing genetic data that two current species where actually only one some time in the past would it represent an observation to you? Or does it has to be a lab experiment (experimental evolution)? Experimental evolution with big animals take ...


0

Rh is just a proteinous(antigenic) factor in red blood cells; not a DISEASE.If it is present in blood you are Rh positive. If not Rh negative.An Rh negative person if exposed to Rh positive blood will form specific antibodies against the Rh antigens. In case of pregnancy, Rh antigens of the foetus do not get exposed to the Rh negative blood of the mother ...


1

Did women evolve to be weaker? No. Humans, in general, are weak in comparison to many animals. We are, in everyday circumstances (including strength training) unable to use 100% of our muscle capacity due to intrinsic properties of the muscle and more central control that is rarely overridden. Our evolutionary relatives are much stronger ...


0

I understand the question as "can you get any animal to have heritable traits selected by humans?" This definition of domestication implies that a population of animals can be bred for a sufficiently long period of time, so that humans can select hereditary traits that fit their needs. Humans could provide selective pressure that creates a new variety with ...


3

There's an issue with what you mean when saying "cold blooded". The correct words you may want to use are homeotherm, poikilothermic, ectotherm, and endotherm. In short… Source of heat endo = inside exo = outside Variance in warmth Poikilo = varies homeo = does not vary Any combination of these two axes exist. For example: If the temperature ...


1

Cypress swamps are an example of tree like plants in lakes. There is even a lake in Louisiana called Cypress Lake


0

Ants, slime molds, and brains. Ants and slime molds use simple rules to generate pretty good transportation networks in an emergent way, and brains wire and rewire themselves constantly(adding/removing edges, but not usually nodes). Evolutionary networks, metabolic networks, and ecological networks are much harder to get concrete data sets from, because ...


2

You will find here a very good overview of the main hypotheses that explain senescence. I am not sure I will answer your question but here are some reactions to your post.. What you say has to do with species selection. Selection selects between various objects/units that differ. These objects may be genes, individuals, populations, species, etc… In other ...


1

The question of 'why are there no/few aquatic trees' can be approached in two ways. 1) Why are land trees tall? 2) Is it harder to be tall in a lake? Land trees are tall to shade competitors and spread their seeds and fruits. To get tall, they need extensive root structures to anchor and provide enough water to the trunk. If there are no competitors to ...


1

Remi.b's answer is great, but here's something less technical if that's what you're looking for: Genetic mutations happen ALL THE TIME. Every time a cell divides, there is an error rate of about one per billion. That's a very low error rate per division, but when you multiply it by the number of divisions, times the number of cells, times the number of ...


2

This reply needs to contain a number of links to qualify each of my claims. Unfortunately this site won't allow me to include more than two links because I am a new user. Please see this post which contains the same response and all the necessary links as well. I would be very careful trusting any claims published by the young earther Jeffrey Tomkins. In my ...


2

In your 5 points you basically cover several concepts of evolutionary biology. 1) The number of mutations depend on mutation rate. The mutation rate varies along genome sequences, species and individuals. According to the recent DECODE study (Kong et al., 2012) a human mother transmit on average 15 mutations to her offspring and a human father transmit on ...


3

I haven't seen this particular film, but other documentaries by Dr. Attenborough are very accurate and well done. In contrast to Remi.b, I'm pretty sure Attenborough referred to the ancient whole genome duplication event in land plants recently discovered in angiosperm genomes by the presence of multiple paralogous genes. The scenario is that at a certain ...


4

Yes, D. Attenborough probably refers to ploidy number Ploidy number Humans for example are 2N (except during the spermatozoid and ovule phase of human existence) meaning that they carry two copies of each autosome (=non-sexual chromosomes). Some species are 1N (haploid), some are 3N (triploid), etc… It would actually be more correct to talk about the time ...


0

I go along with the last entry, death of a host does not signify death of the parasite, and the parasite may benefit from the death of the host if it is able to enter the environment at large. Maybe the parasite was acquired from the soil to begin with. With the death of the host, it is anticipated that the parasite will return to the soil and await a new ...


-3

Since when do humans engage in sexual selection based on intelligence? Humans DO NOT select mates based on intelligence. Just like animals, human sexual selection is primarily based on physical traits. If sexual selection for intelligence exists, why aren't great scientists or geniuses (Edward Witten, Terence Tao) etc sexualized in modern celebrity ...


0

Getting long for a comment I can only comment that evolution does not proceed towards thermodynamic optimum. Adaptation is thermodynamic optimization but evolution is directionless. Otherwise the extant species would not suffer from tradeoffs (which they have even in their usual habitat). Establishment of a self replicating cell may be thermodynamically ...



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