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When you say, why don't we see more sexually reproducing species than asexual, I presume you are referring to bacteria, protists, archaea, some fungi, etc.
Most multicellular organisims do reproduce sexually, which makes sense since an organism would need to be multicellular to have cells specialized for gametes. As you stated, the advantage is that sexual ...
8
Your question is relative to the species concept that you are using. Mayr's biological species concept (BSC) is based on the ability to interbreed; a process-based definition. Most biologists use it, but most taxonomists, who are the people who actually describe species, use some variation of the phylogenetic species concept. The phylogenetic species concept ...
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This just in addition to @anongoodnurse's excellent answer. It was mentioned in the OP that asexual organisms do not undergo recombination; this is not true. Recombination is used for integration of foreign DNA into prokaryotic chromosomes and for repair.
Also, don't underestimate the power of mutational change in rapidly reproducing organisms. While ...
4
It is a transitory state.
During coconut development the "milk" actually starts as a spongy solid a multinucleate endosperm. As the coconut develops it absorbs this tissue. Because of a coconuts hard structure this leaves a cavity since the coconut cannot change shape as the tissue density changes, some fluids including oils are left behind as hte tissue ...
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Not all complex organisms are incapable of regeneration!
The most famous example is probably the axolotl - a salamander that is able to regrow whole limbs or even parts of essential organs like the brain or heart. While it's not yet know how that is possible, there are a lot of researchers looking into it (the genome of this species was fully sequenced last ...
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I was doing some research on this myself and from what I had found, the body has hox genes that direct the formation of body parts. So now the obvious question is that if a body part contains stem cells and hox genes, shouldn't it be able to regenerate a new body? Well, perhaps. But the problem is that as organisms become more complex, the process of the ...
3
Only a matter of definition
It is only a matter of definition. When it comes to sex, there is such a diversity of mating system that it is very hard to make a good definition that won't be challenged by limit cases.
Sexual reproduction can typically be defined based on the presence of meiosis (but again this will lead to limit-cases), on the need for two ...
3
There are various hypotheses and concepts proposed to define a species, but no definitive answer. Mostly a combination of these concepts are used because each hypothesis has exceptions. Classification is constantly being debated, reevaluated, and changed as we learn more. Some of the most notable definitions are:
The is the biological species concept in ...
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Concept of species
First have a look at How could humans have interbred with Neanderthals if we're a different species? to better understand the concept of species.
I will assume that you are using the "biological species definition" which is based on reproductive isolation.
Can any organism possibly have the capability to create a new species every ...
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According to this article from Berkeley, asexual reproduction is:
Any reproductive process that does not involve meiosis or syngamy
Using this definition of asexual reproduction and knowing self-fertilization involves meiosis and syngamy, it is not asexual.
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While I do not know if there is a definitive answer to this question, I suspect that at least part of the answer can be found in the fact that animals typically have much more complex and delicate mechanical interactions in their bodies than plants.
From a mechanical perspective, plants are pretty simple. They move, but generally quite slowly and via very ...
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This question actually does not have an easy answer. As indicated in a previous answer, the 16S rRNA gene is used by many scientists. Since this is a fairly conserved genetic region, mutations in this region can differentiate species phylogenetically, but it is not a foolproof method. For example, several species of Shigella can yield nearly identical 16S ...
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To define, intercalary differentiation or mitosis applies to any cytogenesis through mitosis which arises between different specialised tissues or cells. Spirogyra may undertake either sexual reproduction, should conditions prove to be adverse, or asexual. The latter involves an 'intercalary mitosis'. This entails a fragmentation in the original filament in ...
2
Absolutely impossible. There are several basic reasons:
1. Genetic modification isn't that simple
Not going to go into the mechanics of it, but suffice it to say that you can't perform genetic modification simply by having the cells of one species close to the cells of another. It requires complex techniques, such as shooting the new code at the host ...
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In binary fission, the fully grown parent cell splits into two halves, producing two new cells. After replicating its genetic material, the cell divides into two nearly equal sized daughter cells. The genetic material is also equally split. The daughter cells are genetically identical (unless a mutation occurs during replication).
Source: Binary Fission - ...
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'Possible' is a tricky word here. There are a lot of things that are possible that just don't happen, because they are so exceedingly rare; or that happen but are unknown because they are hard to spot.
As it happens, we know that parthenogenesis-like effects can be induced in humans, because we've done it. If you remember the cloning debacle around Hwang ...
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Sexual vs asexual is not a binary condition it is a spectrum. Many organisms do both and/or a wide range of things in between. One of the most basic is plasmid swapping Bacterial conjunction in unicellular organisms.Even asexual selction has multiple forms of reproduction such as budding vs fission. Exchanging genes can be highly beneficial for multiple ...
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Sexual reproduction is a process where two cells fuse to form a diploid cell. Unicellular organisms (or even multicellular lower organisms like alga, fungi and protists) prefers to reproduce by asexual means under favourable conditions. But when the conditions become unfavourable, they opt to follow sexual reproduction. This suggests, sexual reproduction ...
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It is not necessary that no mutation occurs in the system where no gene recombination or "contaminant" takes place. There are mutations (which are sudden abrupt inheritable changes)
There can be errors in genome which can cause mutations.
Take example of replication of DNA-:
There are many enzymes linked with it : DNA polymerases ( I, II,III) in ...
1
Sexual reproduction probably evolved because an asexually reproducing species of bacteria evolved an evolutionary stable strategy and then there was a rapid change in the environment and only the mutant individuals that could reproduce sexually could evolve fast enough to survive which later evolved into sexually reproducing animals. Also, sexually ...
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