A mass extinction is already happening, as humans relentlessly supplant other major species. Excess human population is also the root cause of global warming, causing the extremes in climate.

Quite a few people believe that a mass extiction is currently underway.

See [thenation.com]

Whether it is connected to climate change or not is open to question ,but it seems most likely.Whether human ingenuity will be sufficient to deal with the problems that climate change will bring the next generations remains to be seen. But they are already condemning us as the most selfish generation ever.

A small mass extinction is already happening. We are loosing species at several orders of magnitude faster than the normal rate.

We are already in it. Insects and amphibians are disappearing at alarming numbers. It's just going to work it's way up from there.

As an animal lover, it sucks.. but I'm also not too concerned. Apart from the planet crumbling, there isn't much that will kill off 100% of the life on Earth. We are putting a hurting on it, but at this point have have to push forward and hope we can develop the technology to balance the planet. Once we do, the remaining life will have population booms and then we will get back into biodiversity.

Gawd, I sure hope they get rid of high mass.

We are not heading towards, we are in the middle of it.
Mass extinctions happens in thousand of years, take time for a species to decline and disappear.
The number of species that went extinct by human arrival (practically all big mammals outside africa), all small insects and rodents extinct by the domestic cat (yes, the kitten is one of the worst hunters that we introduced in many environments), then the agriculture etc. The climate change will be the cherry on the top. Plus the animals that we don't even know we extinguished. There are whole species that lives in one curve of one river in a rain forest, any change on that or polution kills the entire species before we even know it.

I sure fucking hope so.
As long as it's just the humans that go extinct.

I think so but I also think that humans will survive. Might be quite a bit fewer of them but that's certainly not a bad thing.

I think we are in the process of it now. We might not see the 22nd century.

I won't mourn our passing

Yes, climatic change due to mankind's love for burning fossil fuels has been underway since the beginning of the Industrial Age.
Mankind has also been most sadly and steadily pushing innumerable other species to extinction ever since 'civilisation' came into being.
We ARE going to be the cause of the GREATEST by far Mass Extinction ever to occur on this planet IF we don't soon wake up, learn and do something positive and world-wide.

Already underway, climate change is just another phase.

Whilst only a fool would argue that climate change is obviously just random variation, it is a possibility (it takes a specially virulent strain of imbecility to label it a hoax though). So what were left with is an educated gamble. We could throw enough (all possibly?) assets at the problem, worst case outcomes are we couldn't do enough in time and everyone dies, best case is we survive and the world's wealth has been converted into a massive investment in the future. There are plenty of examples out there of the results of technological investment. Or we could ignore the 'hoax'. Best case is the wealthy stay wealthy, the poor stay poor, the hungry, thirsty and sick keep dying. Worst case is everybody gets hungry, thirsty, sick and dead. Ive given it my consideration and decided to give it a go. Somebody tell the rich guys.

Not enough data to say. I'm more concerned about being able to feed and provide energy for the rapidly increasing world population (and shrinking coastlines). When that bubble bursts some serious shit is going to go down, and I fear it could lead to a mass extinction of some sort.

I'm kinda sure that we're already in the middle of one.

Yes.

If you wait long enough, that property in Arizona really will have a beachfront.

No, mass cannot be destroyed. It can be converted to energy in certain circumstances. So mass extinction seems out of the question.

The Komodo Dragons as scientists discovered survived one already hopefully they could survive another.

Yep.

But if the earth becomes as it was when it first formed then I wouldn't give much hope of survival if the planet is a ball of lava and fire and that's not including Co2 in the atmosphere.

And what species would survive if any?