Silurian Period
At the end of the Permian Period which was about 251 million years ago
you can get it at any given time, so its possible. But it doesnt necissarily mean every time you swim
yes of course you can swim when your on your period water prevends the blood from getting released from your body. So as long as your not in the water for a long period of time then your fine.
They Will die
because women sometimes cant swim because of their period, but men can swim all the time
The time it takes to swim 1 mile in the ocean can vary widely depending on a swimmer's skill level, ocean conditions, and currents. On average, a competent swimmer might take anywhere from 30 minutes to an hour. Factors such as waves, tides, and temperature can also significantly affect swim time. It's important for swimmers to assess conditions and swim at a pace that ensures their safety.
they can swim for a long period of time without coming up
Yes, you can. You can even swim while you are in that time if you use tampons. Exercise is good for you, and water will not hurt you.
after a period of time yes
It will Not be safe to swim in the ocean water off the coast of Louisiana, where the oil is leaking and it will not be safe, until they stop the well from leaking, which may not be for quite a long time. I doubt it it will be safe to swim in that location (in the ocean) until 2011 at the earliest.
The dominating animals were marine invertebrates,including crinoids and cystiods,mollusks, and eurypterids.
A wave length.