Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: Muchomank on 02/04/2009 15:17:14

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Muchomank on 02/04/2009 15:17:14

I am doing a case study on the Theory of how the Dinosaurs became extinct. Please may you post all theories that you can find, it would be much if you added reasons supporting and disproving the theory.

Muchomank

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: lyner on 03/04/2009 00:34:31

What happened to personal  work?

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Chemistry4me on 03/04/2009 05:54:58

Yes, wouldn't that be nice! [:)]

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Chemistry4me on 03/04/2009 05:59:41

All kinds of weird and wacky theories:

http://www.infowest.com/life/dinosaurs/extinct.htm

http://www.dinosaurfact.net/extinction/asteroid.php

http://www.dinosaurfact.net/extinction/greenhouseeffect.php

http://www.dinosaurfact.net/extinction/dinosaurstress.php

http://www.dinosaurfact.net/extinction/brainfunctions.php

http://www.dinosaurfact.net/extinction/breakingasteroid.php

http://www.dinosaurfact.net/extinction/supernova.php

http://www.dinosaurfact.net/extinction/caterpillers.php

http://www.dinosaurfact.net/extinction/ozone.php

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Don_1 on 03/04/2009 09:32:20

I googled 'dinosaur extinction theories' and got 345,000 results. in 0.17 secs.

Clever thing this google.

I think I would be inclined to the theory of a meteor collision leading to a failure of plant growth, leading to the slow extinction of large herbivores leaving the carnivores with nothing to eat.

Don't ask which of the 345,000 results this can be found in, I don't know and have no intention of checking to see.

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: blakestyger on 03/04/2009 10:41:51

The asteroid theory has currency at the moment but remember it's not certain - there probably was an asteroid and there was an extinction but causality is yet to be proven.

Also, the KT meteorite has yet to be found - there are indicators though:

High %age of iridium coincident with the period

Glass droplets (tektites)

Shocked quartz and stishovite

Soot from wildfires - estimated at 70 bn tonnes of soot, equivalent to all the forests on Earth today being burned

Crater at Chicxulub (several 100s of metres below surface)

Microdiamonds - caused by high pressures

Tsunami evidence and other rare minerals

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Muchomank on 03/04/2009 12:06:15

thank you blakestyger and chemisty4me for the help
and an answer to other people - i have looked for hours and can only find the main ones such as the impact theory and the Deccan traps.

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: RD on 03/04/2009 13:57:13

Gamma ray burst (hypothesis) for mass extinctions* ...
  http://www.thenakedscientists.com/forum/index.php?topic=21717.msg242872#msg242872


* there were other mass extinctions prior to K-T ...

 [ Invalid Attachment ]

Quote

Marine extinction intensity through time.
Blue graph shows apparent percentage (not absolute number) of marine
animal genera becoming extinct during any given time interval.

http://en.wikipedia.org/wiki/Extinction_event

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: dentstudent on 08/04/2009 12:06:04

This is the real reason

Title: Help! I need to know all theories to how the Dinosaurs became extinct
Post by: Chemistry4me on 08/04/2009 12:07:22

Brilliant!