Here ’s a fun way to opine about the timescales involved in evolution : shark have been around so long that they have likely been around the Milky Way twice .
Just as the Earth turn out around the Sun , the Sun ( with all the planet in tow)rotatesaround the center of the galaxy . We ’re moving at around 828,000 kilometers ( 514,500 miles ) per time of day , at a distance of about 28,000 easy - age from the galactic center . We ’ll save you the trouble of endeavor to retell the exact figure of Pi from memory and performing your own calculations and let out that this mean we take around230 million years(estimates put it somewhere between 225 to 250 million Earth twelvemonth ) to complete an ambit around the galactic center of the Milky Way .
That ’s an unfathomable amount of clip . To make it even more unfathomable ( or possibly less , we ca n’t quite decide ) that means sharks , which evolved around 450 million long time ago , have hitched a lift on our satellite around the galaxy twice . To put it another more flattering way , they are around twogalactic yearsold .
A lot has shift on Earth in those two galactic years . Not to sound like a hack comedian attempting a " yo momma " caper , but sharks are so onetime they develop before trees , which first arrive on Earth around390 million years ago . While sharkschangedbut ultimately still carry on being sharks , the first dinosaurs develop from lounge lizard and enjoyed a nerveless 165 million eld before being wiped out .
Sharks continued to not get wiped out during another four extinction issue , potential thanks to their diverseness .
" I guess it is safe to say that it is partly because shark are capable to exploit different parts of the water pillar - from rich , dark oceans to shallow sea , and even river system , " Emma Bernard , a conservator of fossil fish at the Natural History Museumsaid in a piecefor the museum . " They exhaust a wide change of food , such as plankton , fish , crabs , stamp and whales . This multifariousness mean that shark as a mathematical group are more likely to survive if things in the oceans change . "
During this metre , if they ’d take the time to make telescopes as they zipped around the coltsfoot , they ’d have ensure therings of Saturnbe created .
