Why did non-aquatic animals evolve to not being able to drink salt water?
>All living organisms need water
>sea water is the most abundant
>Evolution
>???
>Can't drink salt water anymore
What the fuck happened?
>>7718994
>sea water is the most abundant
globally, but necessarily locally
if you live in an environment where most of the water comes from rain and rivers you drink that
>>7719006
Yeah but there are more beaches than there are rivers and lakes .So salt water should be somewhat more accessible atleast not in the mainland.
>>7719039
>atleast not in the mainland.
There are lots of creature in beaches that can drink salt water, like crabs and such.
Most land animals spent at least part of their evolutionary history inland, and thus became dependent on fresh water.
>>7719039
The coast is not in range of most land animals.
>>7718994
Some guy tested this with his family. They lived on a boat for a full year, drinking nothing but seawater and fish-blood. Turns out human beings can live with that diet - one more proof that at some point in time we were marine mammals.
>>7719453
Is it the dude who enema-ed himself
>>7719453
That's not in any way even suggestive that we were marine mammals.
Drinking salt water will leave you dehyrdated... but there is a limit to how badly. For typical ocean water, you can live off it (but poorly) for an indefinite period as long as you're eating some food, which will also have good water content.
> http://news.nationalgeographic.com/news/2014/02/140203-man-adrift-sea-survival-oceans-medicine-science/
Saltwater fish can separate out the salt and water in their gills and thus actually drink freshwater in the ocean so to speak. Obviously we can't do that anymore.
Even whales don't drink seawater (not on purpose that is); it's thought that they mostly get their water as part of their diet (from the tissues of prey) and thus can actually die of dehydration out in the ocean if they're starving. They can handle a little bit, and have better kidneys than us for dealing with salt, but definitely can't just drink it ad-lib.
Freshwater fish don't drink water either for that matter; it's simply absorbed through their skin.
>>7719518
>http://news.nationalgeographic.com/news/2014/02/140203-man-adrift-sea-survival-oceans-medicine-science/
That doesn't mention drinking saltwater at all. It says he drank rainwater and the blood of birds and turtles. None of which is terribly salty.
>>7719039
>Yeah but there are more beaches than there are rivers and lakes
[citation needed]
I'm pretty sure there's more freshwater shoreline than saltwater shoreline.
Pic related is a tiny fraction of the total rivers and streams in the U.S.
>>7718994
I can imagine freshwater simply is the better choice because its mor efficient in fullfilling the water tasks of being essentially a container for all kinds of molecules the body has to manage.
If water is already saturated with salts it can only hold a small amount of the stuff your body wants to get rid of/transport.
I know that there are terrestrial plants that have mechanisms to manage high salt concentration (halophytes) but it costs energy and adaption.
I guess to get this thread any further we need to know how marine animals handle salt in their organism.
Do see leopards and the likes drink salt water?
