The Instigator
Dagolas
Pro (for)
Losing
0 Points
The Contender
bluesteel
Con (against)
Winning
19 Points

Megalodon still roams the seas

Do you like this debate?NoYes+2
Add this debate to Google Add this debate to Delicious Add this debate to FaceBook Add this debate to Digg  
Vote Here
Pro Tied Con
Who did you agree with before the debate?
Who did you agree with after the debate?
Who had better conduct?
Who had better spelling and grammar?
Who made more convincing arguments?
Who used the most reliable sources?
Reasons for your voting decision - Required
1,000 Characters Remaining
The voting period for this debate does not end.
Voting Style: Open Point System: 7 Point
Started: 8/6/2011 Category: Science
Updated: 5 years ago Status: Voting Period
Viewed: 3,873 times Debate No: 17799
Debate Rounds (5)
Comments (11)
Votes (3)

 

Dagolas

Pro

I believe that there is a strong possibility that Carcharodon megalodon, or Carcharocles megalodon, still exists. This breed of shark is rumoured to be extinct. It would have lived in prehistoric times (Cenozoic Era), and been about more than 16 metres long (52ft).

Sources:
http://en.wikipedia.org...
bluesteel

Con

Thanks for the topic Dagolas.

According to the ReefQuest Centre for Shark Research, the Megalodon "extinction [occurred] in the Plio-Pleistocene (1.6 million years ago)." [1] The ReefQuest Centre explains that we know Megalodon is extinct because we find fossilized remains of its teeth throughout the entire world, suddenly ending 1.6 million years ago.

The ReefQuest Centre answers many of the main arguments claiming that Megalodon is still alive.

1) Only 5% of the deep sea has been explored

Reefquest Centre says, "Megalodon seems to have been limited to warm, shallow seas near coastlines and there is no evidence it had any specializations that would have enabled it to survive the intense cold of the deep-sea." [2] The fact that no one has seen a giant shark (large enough to swallow a rhinoceros whole) swimming in shallow waters is pretty good evidence of its extinction.

2) The rest are just different appeals to ignorance.

What caused Megalodon's extinction?

Answer: the closing of the Central American Seaway (through the land formation of the Isthmus of Panama), which did 3 things.

1. Ocean cooling

The Isthmus of Panama altered ocean currents by cutting off the formerly open Central American Seaway, which resulted in a significant cooling in ocean temperatures during the Pliocene Era and the formation of ice sheets at the poles. [3] The colder temperatures significantly reduced the number of waters that such a large cold blooded animal could survive in and reduced suitable nursery sites for breeding. Fossil evidence confirms a SIGNIFICANT thinning out of the Megalodon population during the Pliocene. [4]

2. Food supply dwindled

During the Miocene, there were 20 species of large cetaceans for the Megalodon to prey upon. However, during the Pliocene, most went extinct or moved elsewhere. Fossil records show that whale migration patterns changed during this period to more arctic regions, eliminating these large animals as a potential food source to the Megalodon. [5] A large predator needs large prey, but since small prey were either dying or moving to more arctic regions, large prey were also either dying or moving to waters where the Megalodon could not follow.

3. New competition

During the Pliocene, a large species of killer whale evolved to compete for the Megalodon's dwindling food supply. [6] Killer whales were faster than the sharks, in addition to being able to sustain colder climates, so the killer whales could hunt the Megalodon's food but the Megalodon could not hunt all of the killer whales' food, meaning the ultra large orcas were better predators. Faced with an already dwindling food supply and an inability to breed, the Megalodon ultimately succumbed to these better predators.

It's pretty simple; a body with a large size has a number of tradeoffs - that large size requires more resources, is more inefficient, and is more difficult to heat. Without large prey animals, the large size did not have any benefits over predators with smaller sizes, ultimately leading to extinction in a battle for the survival of the fittest.

[1] http://www.elasmo-research.org...
[2] http://www.elasmo-research.org...
[3] http://www.whoi.edu...
[4] http://www.elsevier.com...
[5] http://www.sdnhm.org...
[6] http://www.science.smith.edu...
Debate Round No. 1
Dagolas

Pro

I am proved wrong. I have nothing more to say, this beast is extinct.
bluesteel

Con

cool, i guess....
Debate Round No. 2
Dagolas

Pro

Dagolas forfeited this round.
bluesteel

Con

My opponent conceded already...
Debate Round No. 3
Dagolas

Pro

Dagolas forfeited this round.
bluesteel

Con

Forfeit - vote con
Debate Round No. 4
Dagolas

Pro

Dagolas forfeited this round.
bluesteel

Con

My opponent gave up - vote con.
Debate Round No. 5
11 comments have been posted on this debate. Showing 1 through 10 records.
Posted by Man-is-good 5 years ago
Man-is-good
It looks like bluesteel won already...
Posted by Dagolas 5 years ago
Dagolas
Indeed. My opponent has posted too many reliable sources.
Posted by alex0828 5 years ago
alex0828
Um pro, did you just give uP?
Posted by Man-is-good 5 years ago
Man-is-good
Bluesteel, I must say you did an impressive job. I was obliged to take the debate, but at least a far more formidable debater than me took it.
Posted by bluesteel 5 years ago
bluesteel
This is actually why people coined the phrase - "exception that proves the rule." There's only one example of fossil predictions of extinctions being wrong in human history and we corrected it using improved technology 75 years ago. If anything, that's a pretty miraculous record for fossil science; 99.999% accuracy.
Posted by bluesteel 5 years ago
bluesteel
@blackhawk

That's answered here as well: http://www.elasmo-research.org...

It's basically just false induction - just because one species that was thought to be extinct was later found alive, doesn't mean this one will be. It's a false analogy because enormous sharks would be harder to miss than a tiny fish. Megalodon teeth fossils are also much more common than coelacanth fossils were, so their disappearance 1.6 million years ago looks much more damning. And lastly, the coelacanth was discovered in 1938, when ocean sciences were first emerging with new technologies, so it made it inevitable to discover said fish in shallow waters off the coast of Africa. The fact we haven't found Megalodon's in shallow waters in spite of having explored nearly all of them and improved our technology significantly is pretty telling.
Posted by blackhawk1331 5 years ago
blackhawk1331
The only thing I want to comment on is Con's point of a lack of fossils. The coelacanth was thought to be extinct until relatively recently when a live one turned up, and we started finding them.
Posted by Rockylightning 5 years ago
Rockylightning
I believe an octupus's garden exists. I heard it in a beatles song. The seas are yet to be completely explored so we may never know. I'd like to be, under the sea, in an octupuses garden, in the shade.
Posted by Dagolas 5 years ago
Dagolas
For the seas are yet to be completely explored.
3 votes have been placed for this debate. Showing 1 through 3 records.
Vote Placed by Zarroette 2 years ago
Zarroette
DagolasbluesteelTied
Agreed with before the debate:--Vote Checkmark0 points
Agreed with after the debate:--Vote Checkmark0 points
Who had better conduct:-Vote Checkmark-1 point
Had better spelling and grammar:--Vote Checkmark1 point
Made more convincing arguments:-Vote Checkmark-3 points
Used the most reliable sources:-Vote Checkmark-2 points
Total points awarded:06 
Reasons for voting decision: ff
Vote Placed by Man-is-good 5 years ago
Man-is-good
DagolasbluesteelTied
Agreed with before the debate:--Vote Checkmark0 points
Agreed with after the debate:-Vote Checkmark-0 points
Who had better conduct:-Vote Checkmark-1 point
Had better spelling and grammar:--Vote Checkmark1 point
Made more convincing arguments:-Vote Checkmark-3 points
Used the most reliable sources:-Vote Checkmark-2 points
Total points awarded:06 
Reasons for voting decision: Excellent argument made by Bluesteel who dismantled Dagolas' appeal to ignorance (which he laid out in the comments page) through strong argumentation and use of reliable, secure sources.
Vote Placed by darkkermit 5 years ago
darkkermit
DagolasbluesteelTied
Agreed with before the debate:-Vote Checkmark-0 points
Agreed with after the debate:-Vote Checkmark-0 points
Who had better conduct:-Vote Checkmark-1 point
Had better spelling and grammar:-Vote Checkmark-1 point
Made more convincing arguments:-Vote Checkmark-3 points
Used the most reliable sources:-Vote Checkmark-2 points
Total points awarded:07 
Reasons for voting decision: PRO just fails.