What are the odds that another organism mutates at around the same time/when the first one hasn’t died yet and that that mutation changes the second organism into the exact same species as the first one (changes the same dna bases) AND that those 2 organisms find each other and have sex?
In: 3
Species don’t change over the course of a single generation. It would take a population as a whole many years to get to a point where it couldn’t reproduce with the original members of the group, so this would not actually be a problem.
[removed]
Let’s say that there is a creature, like a bug, that mutates and becomes a different species. This new species of bug might be able to reproduce sexually, which means that they would need to find another bug of the same species to have babies with.
Now, when two bugs have sex, they each contribute half of their genetic material to make a baby bug. This means that the baby bug will have some characteristics from each of its parents. But, even though the baby bug might be similar to its parents, it will still be its own unique creature, and it might have some different characteristics than its parents.
As for the odds that another bug would mutate and become the exact same species as the first one, it’s very unlikely. Mutations are random events, and it’s not very likely that two bugs would mutate in exactly the same way at the same time. Even if two bugs did mutate and become the same species, they would still have to find each other and have sex in order to make baby bugs. So, overall, the odds of all of these things happening are very, very low.
That’s not how mutations work. It’s not like some homo erectus gave birth to a fully modern human and then there was just one modern human around. Mutations happen gradually, a few per generation, over many many *many* generations. For humans, that’s many hundreds of thousands of years. During all of that time, the different organisms of the same species with different mutations are still interbreeding and sharing those mutations with each other.
Just to give you an idea, humans and neanderthals diverged from their common ancestor somewhere around 600-700 thousand years ago, and over 500,000 years later, they were still similar enough to interbreed despite being clearly distinct, separate species at that point.
There’s a bit of a misunderstanding here. No organism mutates into a different species. You can think of species as a snapshot in time of what organisms can reproduce with each other today. You can’t reproduce with a gorilla today, so you’re a different species than the gorilla. But maybe your Great Great Great……Grandfather and the gorilla’s Great Great Great…..Grandmother could have. That is your common ancestor. It’s the many generations that separate us from the gorillas that make us different species. It doesn’t happen over a single generation. So there is no answer to your question because it’s really a false premise.
When the size of a USB port changed ever so sightly, the USB would still fit… Do it a million times and it doesn’t.
The species changes gradually and become less and less compatible every time. That’s why horses and donkeys can still have a baby, still sightly compatible.
“Species” just means “group of individuals that can mostly breed successfully with each other” and it’s really just a helpful descriptive term rather than any kind of fundamental natural law. We all have different genes from everyone around us but most of us do mange to pass on our genes. This mix of everyone mating keeps the population more or less similar.
Mutations happen in every generation. Most of these have no obvious effects, and it is only when many, many mutations have happened in a population over time that we start to see some changes in the group of individuals with those mutations. Because the individual changes are very small and each in isolation brings no particular advantage or disadvantage, they can spread throughout that population over time, meaning that the species itself slowly becomes another species (ie different from and unable to mate with its distant ancestors even if they invent a Time Machine). In other words, evolution happens at the group level, not at the individual level.
If some groups of a species are isolated from each other, this “drift” can happen differently in the different groups, leading to what was one species becoming two species that, even if brought back together, will not breed, either because they are physically unable to, or because they just don’t recognise each others’ mating behaviours.
Sometimes if different species do come back together before they have diverged too far, they can still breed, leading to “cross” species, such as https://en.wikipedia.org/wiki/Grizzly–polar_bear_hybrid
This can occur in many different ways but basically you have a mechanism where one organism borrows some of the genes it uses to produce offspring from another. Originally only one member of the species would have had this ability basically by accident, but over time that trait would turn them into a new species where every member does it and they would functionally be something like [simultaneous hermaphrodites](https://en.wikipedia.org/wiki/Reproductive_system_of_gastropods#Simultaneous_hermaphrodites).
Over the generations at some point you might see an evolution of sexes where one half of the population specializes in producing offspring while the other half specializes in something else, losing the ability to carry children completely, although this varies from one species to the next. There’s no inherent reason for only two sexes and many species exist with more than two sexes, like [Tetrahymena thermophila](https://en.wikipedia.org/wiki/Tetrahymena#T._thermophila:_a_model_organism_in_experimental_biology) with seven different sexes that reproduce in 21 different combinations. Basically the point of sex is to ensure you can’t mate with your own type or just clone yourself because that tends to be bad for diversity and fighting disease (a virus that finds a bunch of clones in a room will have a better day than one that finds a bunch of somewhat different individuals).
Latest Answers