Also note that the climate of Africa (for example) was not unchanging but has varied over the past several million years. Total forest coverage versus open grassland has likewise varied over time, which may be relevant for preferred survival of some species of hominins versus others. It's also...
Obviously embryonic development can be affected by the local environment. In placental mammals, where the embryo is inside the mother's body, it can be affected by chemical substances (like alcohol or thalidomide, which cause developmental disorders) or even by a physical trauma. And to say DNA...
It seems to me that a problem with the balloon analogy is that while all points on the surface of the balloon are equivalent, the "center of expansion" of the balloon is unique. But that center is not actually on the balloon of course, and is "outside" the balloon universe. Since this whole...
In the original figure in this thread, an example was shown of fruit flies that were already highly inbred, so the father and mother were each mostly homozygous, at least on the X chromosome. In that specific example, physical recombinantions in the parental germ lines would not yield any...
Wild relatives are not automatically more diverse, and there are examples of wild populations with reduced diversity (African cheetahs apparently). They are usually more diverse simply because they are not under human selection for a limited range of traits. Greater genetic diversity simply...
Whether interspecific hybrids are fertile or sterile depends to some extent on the definition of a species. If one defines a species as organisms that look very different, then things someone has decided to call different species may actually not be, and may interbreed perfectly well - it...
Another way to think about it is that the genome is neither a blueprint or a map, it's more like a set of Ikea instructions.
1. Make lots of cells by mitosis.
2. Now there are a lot of cells. If you are a cell on the surface of the ball of cells, turn on gene 125. If you are inside the ball of...
Actually many plants, especially those that have been domesticated, are polyploid, having more than two copies of their entire genome in each cell. Thus their genetics tends to be more complex than humans', not less!
The so-called Modern Synthesis includes our knowledge of genetic inheritance and now also the nature of genetic information (DNA usually, RNA sometimes) and genetic variation. With molecular tools we can see examples of "evolution" in progress, such as novel gene duplications or losses (such as...
Since there is usually at least some amount of water vapor in air, virus particles in the general environment might well retain closely bound water molecules required to stay folded correctly. That would be a function of the actual partial water vapor pressure and the non-covalent binding...
The comparative genomics studies described in the various replies do of course have another caveat, which is that they identify genomic regions required in at least most of the species being compared. If there are regions of our genome required in us but not in mouse (novel transcriptional...
Domesticated crops have been bred for many many generations. While they have plenty of genetic variation, they presumably won't have the broader range of variation found in their wild ancestors since the whole point of domestication is to standardize the plant for certain desirable (to farmers)...
The definitions are ultimately arbitrary. Coding sequence is defined as that of the mRNA, which is the reverse complement of the DNA strand which was read and transcribed by RNA polymerase, so by definition the physical strand of DNA read is the non-coding strand. For simplicity's sake, we...
In other words, there is recombination in the founders, but since they are homozygous (according to the figure shown), the recombination doesn't change the information content of their genomes so it doesn't "look like" any recombination happened. Physically it did, recombination is probably...
As Bandersnatch and Jim said, your friend shares approximately 1/4 of each of her grandparents' genomes including the paternal grandfather. As you suspected, the sex chromosomes behave a bit differently. Your friend is female, so received one X from each parent. Her paternal X however came from...