the native biosphere would have very little defense against us.
Why is it that way around, instead of “we would have very little defense against the native biosphere?” Especially considering the native biosphere has the home court advantage, it’s already well adapted to the environment it’s in and has a planet’s worth of diversity to draw on when dealing with new competitors.
A new biosphere often has zero resistance against an invasive species.
All those tricks that the local biosphere have are targeted against other parts of the biosphere. It’s called the co-evolutionary arms race. Prey species get better at defending themselves, and predators get better at targeting weak points in their prey. Predators can become super specialized. And in this specific case, herbivores can be considered predators to plant species.
An invasive species slips in when there is no local predator to eat them. Often because no predator can adapt to the new invasive species.
To back this all up, just look at the history of humanity transporting plants and animals all over the place and fucking shit up, all because we figured out the absolute best defense against our own predators, being too fucking smart for our own good.
The only way an alien biosphere could defend itself against us is if the planet it was on had an excess of heavy metals or other poisonous elements like arsenic that became a part of the biosphere itself.
“Invasive” species here on Earth are invasive because they turn out to be more highly adapted to the new environment they find themselves in than the existing “native” species. That’s only possible because Earth has a lot of similar habitats, allowing species in different areas to try out a variety of different adaptations that can potentially end up being very useful in the new environments they get plopped down into. They happen to have hit on some strategy that’s better than what the natives have come up with yet.
In the case of a completely alien planet with its own well-established biosphere that’s likely not going to be the case. The habitats and niches available there are going to be different from whatever we’ve got on Earth, so the life we bring from Earth isn’t going to have any ready-made superior strategies to deal with them. The local native life, on the other hand, has had billions of years to come up with ways to make a living there.
Again, you’re ignoring the fact that the entire biosphere experiences co-evolution, This is why an invasive species is a problem. It was not part of the evolutionary arms race in that environment. It means that the highly specialized attacks that the plants and animals have against each other, might not work at all against the invader.
The billions of years of coming up with ways to make a living there, is actually billions of years of coming up with attacks specialized to exploit weaknesses in each other.
Take viruses as an example. They are often highly specialized to attack specific protein clusters on the outside of cells. Now, sometimes, through some random mutation, they can attack a slightly different protein structure and jump to a different host species, where they run rampant.
That said, alien viruses would likely not be an issue to either side. They’re too specialized. Bacteria, on the other hand, that might pose a problem. But can be compensated for.
But other than that. Humans are very good at being an invasive species. We cheat. If there is anything edible on the planet, we’ll find it. And the planet wouldn’t know what hit it.
Again, the only way the planet’s biosphere could keep us out, is if it was fundamentally incompatible. Like if it had an atmosphere without oxygen, or if every plant and animal had lead or arsenic in their biochemistry.
It hardly needs to be a difference so extreme. If the atmosphere had half the oxygen that Earth’s does, Earth life would struggle badly and most species would simply fail to make a go of it - it’d be like living at 5.5km altitude. The highest human settlement on Earth is at 5km and the people there suffer from chronic health problems, it’s a gold mining settlement that wouldn’t have anyone living there if they couldn’t earn a ton at it. But for the native life that’s just Tuesday.
To back this all up, just look at the history of humanity transporting plants and animals all over the place and fucking shit up, all because we figured out the absolute best defense against our own predators, being too fucking smart for our own good.
You’re assuming this is the norm rather than something being transported and not able to survive in the new environment. Kudzu, as an example, is an invasive plant from Japan that has taken over the Southern US due to lack of insects and animals that eat it. But if Kudzu was brought to the Amazon instead, it likely wouldn’t survive due to the high acidity of the soil. The plants there are specialized and it’s unlikely for a plant without this specialization being able to widely spread.
Why is it that way around, instead of “we would have very little defense against the native biosphere?” Especially considering the native biosphere has the home court advantage, it’s already well adapted to the environment it’s in and has a planet’s worth of diversity to draw on when dealing with new competitors.
A new biosphere often has zero resistance against an invasive species.
All those tricks that the local biosphere have are targeted against other parts of the biosphere. It’s called the co-evolutionary arms race. Prey species get better at defending themselves, and predators get better at targeting weak points in their prey. Predators can become super specialized. And in this specific case, herbivores can be considered predators to plant species.
An invasive species slips in when there is no local predator to eat them. Often because no predator can adapt to the new invasive species.
To back this all up, just look at the history of humanity transporting plants and animals all over the place and fucking shit up, all because we figured out the absolute best defense against our own predators, being too fucking smart for our own good.
The only way an alien biosphere could defend itself against us is if the planet it was on had an excess of heavy metals or other poisonous elements like arsenic that became a part of the biosphere itself.
We would be the “new biosphere”, though.
“Invasive” species here on Earth are invasive because they turn out to be more highly adapted to the new environment they find themselves in than the existing “native” species. That’s only possible because Earth has a lot of similar habitats, allowing species in different areas to try out a variety of different adaptations that can potentially end up being very useful in the new environments they get plopped down into. They happen to have hit on some strategy that’s better than what the natives have come up with yet.
In the case of a completely alien planet with its own well-established biosphere that’s likely not going to be the case. The habitats and niches available there are going to be different from whatever we’ve got on Earth, so the life we bring from Earth isn’t going to have any ready-made superior strategies to deal with them. The local native life, on the other hand, has had billions of years to come up with ways to make a living there.
Again, you’re ignoring the fact that the entire biosphere experiences co-evolution, This is why an invasive species is a problem. It was not part of the evolutionary arms race in that environment. It means that the highly specialized attacks that the plants and animals have against each other, might not work at all against the invader.
The billions of years of coming up with ways to make a living there, is actually billions of years of coming up with attacks specialized to exploit weaknesses in each other.
Take viruses as an example. They are often highly specialized to attack specific protein clusters on the outside of cells. Now, sometimes, through some random mutation, they can attack a slightly different protein structure and jump to a different host species, where they run rampant.
That said, alien viruses would likely not be an issue to either side. They’re too specialized. Bacteria, on the other hand, that might pose a problem. But can be compensated for.
But other than that. Humans are very good at being an invasive species. We cheat. If there is anything edible on the planet, we’ll find it. And the planet wouldn’t know what hit it.
Again, the only way the planet’s biosphere could keep us out, is if it was fundamentally incompatible. Like if it had an atmosphere without oxygen, or if every plant and animal had lead or arsenic in their biochemistry.
It hardly needs to be a difference so extreme. If the atmosphere had half the oxygen that Earth’s does, Earth life would struggle badly and most species would simply fail to make a go of it - it’d be like living at 5.5km altitude. The highest human settlement on Earth is at 5km and the people there suffer from chronic health problems, it’s a gold mining settlement that wouldn’t have anyone living there if they couldn’t earn a ton at it. But for the native life that’s just Tuesday.
You’re assuming this is the norm rather than something being transported and not able to survive in the new environment. Kudzu, as an example, is an invasive plant from Japan that has taken over the Southern US due to lack of insects and animals that eat it. But if Kudzu was brought to the Amazon instead, it likely wouldn’t survive due to the high acidity of the soil. The plants there are specialized and it’s unlikely for a plant without this specialization being able to widely spread.