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3

This is an interesting question, and it's been subject to a fair amount of research. From an epidemiological perspective, most rabies outbreaks have been studied in dogs. Among domestic dogs, the R0, or basic reproduction number, of rabies is usually quite low—estimated to be around 1.2 in rural sub-Saharan Africa, and <2 in most historically observed ...


1

I think that you are talking about what are sometimes called "rates of evolution", see also https://www.thenakedscientists.com/articles/questions/do-smaller-organisms-evolve-faster. That wiki is a collection of info of interest mostly to specialists, but the blog post may be helpful. The short answer is that there is a strong negative correlation between ...


1

A lack of strong evidence causes the field to be mostly hypothetical. Detailed pre-cambrian fossils are necessary, from the 1bn-600 million years ago, to find a protostome - deuterostome ancestor. Genetic data is also inconclusive. A search for bilateral common ancestor gives i.e. dev.biologists.org/content/129/13/3021 It's a summary of research, where the ...


-1

This was a question on the 2016 Toronto Biology Exam, precisely question 42. Though the question was asked vaguely, d is the best answer. It's quite obvious that if animals are in water, fins will eventually evolve to improve fitness, that's pretty obvious. However, if they are both in water, why are their fins different? This touches on the more complex ...


5

High temperatures means that lots of energy is available in the environment. This energy speeds up chemical reactions, and make possible some reactions that wouldn't happen at all at lower temperatures. In particular, proteins can adopt new shapes as temperatures get higher. It's the misshapen proteins rather than the temperature per se that kills the ...


1

Your first option is the correct interpretation. The correlation you observe in the raw data is the effect of phylogeny. Without using PICs, you might expect to see phylogenetic autocorrelation, i.e. your raw data correlate as a function of the amount of shared evolutionary history between different species. Using PICs is one way of testing whether the ...


3

The topic is called Peto's paradox, you can find references to studies on the wiki page, here's a summary: A rat cell is more likely to get cancer than an elephant cell in the same time span. Mice have cancers in 2 years as often as humans have in 60 years. Studies find that 4 ton elephants have only 4 times more blood cells than a 12 gram shrew. They ...


1

We can say that brain and our nerve system is the first system in embryo that starts to develop and as you said this system is continuing to develop until after birth. So here is a question that why our brain don't develop completely before the birth ? Evolution has gone so far as to limit the development of the brain in the human embryonic phase and to ...


1

Their arguments for increased telomere length in lab mice are: Rate of tumour formation is dependent on the number of cells within an organism. Additionally, tumours take time to form. Therefore, small animals that only need to reproduce early in life, like lab mice, are less prone to tumours and there is then less selective pressure favouring telomere ...


1

"Yes" is the simple answer to the first part of your question. HIV, "Typhoid Mary", maybe Covid19, and other examples have been given. The second part of your question, I am asking this as I am thinking whether this means certain disease symptoms are mechanisms resulted from evolution to protect the "greater good", i.e. killing the patient to avoid ...


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