# Dinosaur extinction - hot or cold ? **URL:** \ **Category:** Factual Questions\ **Created:** [October 3, 2015, 6:12pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391 "2015-10-03T18:12:43Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![MrQwertyasd](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@MrQwertyasd](https://boards.straightdope.com/u/MrQwertyasd)\ **Post date:** [October 3, 2015, 6:12pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/1 "2015-10-03T18:12:43Z")
Scientists can’t seem to come to a definitive conclusion about whether dinosaurs where killed by a global firestorm after an impact event, or by the nuclear winter style cold that followed it? Which is it ? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2015, 7:24pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/2 "2015-10-03T19:24:54Z")
It’s not an either/or question. Many were no doubt killed in the initial firestorms. Many of those that survived would have died of starvation when dust and ash clouds prevented plants from growing. There were lots of detrimental effects going on, which is the reason the event was so lethal. It is thought that acid rain may also have had an effect. New evidence suggests that the impact may have triggered an increase in the vast lava flows that formed the Deccan Traps in India, causing further extinctions. ---
**Author:** ![barbitu8](https://avatars.discourse-cdn.com/v4/letter/b/839c29/32.png) [@barbitu8](https://boards.straightdope.com/u/barbitu8)\ **Post date:** [October 3, 2015, 9:07pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/3 "2015-10-03T21:07:13Z")
> [@Colibri](#): > > It’s not an either/or question. Many were no doubt killed in the initial firestorms. Many of those that survived would have died of starvation when dust and ash clouds prevented plants from growing. > > There were lots of detrimental effects going on, which is the reason the event was so lethal. It is thought that acid rain may also have had an effect. New evidence suggests that the impact may have triggered an increase in the vast lava flows that formed the Deccan Traps in India, causing further extinctions. How did small herbivorous mammals survive? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 3, 2015, 9:22pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/4 "2015-10-03T21:22:27Z")
Mostly, by luck, aided by the fact that a small animal can adapt more easily to food shortages, and a larger population would give them more chances to roll the dice. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 3, 2015, 9:26pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/5 "2015-10-03T21:26:47Z")
> [@barbitu8](#): > > How did small herbivorous mammals survive? By eating dead dinosaurs. Literally in some cases, but mostly because smaller animals require fewer resources to survive. ---
**Author:** ![smithsb](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/smithsb/32/12107_2.png) [@smithsb](https://boards.straightdope.com/u/smithsb)\ **Post date:** [October 3, 2015, 9:29pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/6 "2015-10-03T21:29:32Z")
> [@Colibri](#): > > It’s not an either/or question. Many were no doubt killed in the initial firestorms. Many of those that survived would have died of starvation when dust and ash clouds prevented plants from growing. > > There were lots of detrimental effects going on, which is the reason the event was so lethal. It is thought that acid rain may also have had an effect. New evidence suggests that the impact may have triggered an increase in the vast lava flows that formed the Deccan Traps in India, causing further extinctions. New evidence? I read a book on just that over a decade ago. It also pinned previous mass extinction events to massive volcanic vent activity; one I remember was tied to an event in Siberia. Give me a few hours and I’ll dig up the book. The author must be spitting mad regarding this\*\* NEW\*\* evidence. ---
**Author:** ![smithsb](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/smithsb/32/12107_2.png) [@smithsb](https://boards.straightdope.com/u/smithsb)\ **Post date:** [October 3, 2015, 9:40pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/7 "2015-10-03T21:40:50Z")
Author was Gerta Keller, I bleieve. Some of the main evidence for the extinction coming directly from the eruptions was that extinctions were already going on before the impact date. Also, a Steven Schultz writes on it as far back as 2003. > **[Gerta Keller](https://en.wikipedia.org/wiki/Gerta_Keller)** > > Gerta Keller (born 7 March 1945) is a geologist and paleontologist who contests the Alvarez hypothesis that the impact of the Chicxulub impactor, or another large celestial body, directly caused the Cretaceous–Paleogene extinction event. Keller maintains that such an impact predates the mass extinction and that Deccan volcanism and its environmental consequences were the most likely major cause, but possibly exacerbated by the impact. > Keller was raised in Switzerland on a dairy farm, the sixth o... Virginia Tech geologist Dewey McLean is also a proponent of the eruption theory more than a decade ago. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2015, 9:53pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/8 "2015-10-03T21:53:17Z")
> [@barbitu8](#): > > How did small herbivorous mammals survive? Mammals at the time were mostly small and nocturnal. They probably often lived in burrows where they would have been shielded from the worst effects. They probably fed on insects, worms, and maybe seeds, which would have still been available after the catastrophe. Freshwater animals, including ones up to the size of crocodiles, also survived pretty well, again probably because their habitat provided some protection. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 3, 2015, 9:59pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/9 "2015-10-03T21:59:05Z")
> [@smithsb](#): > > New evidence? I read a book on just that over a decade ago. It also pinned previous mass extinction events to massive volcanic vent activity; one I remember was tied to an event in Siberia. Give me a few hours and I’ll dig up the book. The author must be spitting mad regarding this\*\* NEW\*\* evidence. Relax.😉 The idea that the Deccan traps eruptions were tied to the end Cretaceous extinctions has been around for a long time. There’s been an ongoing debate between proponents of the asteroid theory and those for volcanism. Arguing against the volcanism theory was the fact that the eruptions started before most of the extinctions took place. The new bit is [evidence that the asteroid impact may have intensified eruptions that were already going on](http://www.ibtimes.co.uk/dinosaur-extinction-asteroid-impact-triggered-massive-volcanic-eruptions-deccan-traps-1522040), producing a double-whammy. This idea is not entirely new either; what’s new I think is definite evidence to support it. ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [October 3, 2015, 10:37pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/10 "2015-10-03T22:37:31Z")
When Chicxulub was first discovered, there was a certain amount of speculation about it being related to the Deccan traps because in addition to the coincident timing, they were also on roughly opposite sides of the Earth. However, as the paleogeographical data got better it turns out they were pretty far off from being antipodal (about 5,000KM) and plus the exact mechanism for the impact punching all the way though the Earth and somehow affecting the other side was always pretty iffy. So the timing was mostly written off as a coincidence, relevant only in that the 1-2 punch of the impact and volcanism might have been what made it a truly major extinction event. It sounds like the new theory is somewhat resurrecting the connection, but focusing more on seismic waves propagating across the surface of the Earth meeting at a vaguely antipodal point. Of course that makes it an even bigger coincidence since not only did the big impact come at a time when there was already large scale volcanism going on, but it also hit at a location that made the volcanism worse. ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [October 3, 2015, 11:39pm UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/11 "2015-10-03T23:39:45Z")
> [@GreasyJack](#): > > When Chicxulub was first discovered, there was a certain amount of speculation about it being related to the Deccan traps because in addition to the coincident timing, they were also on roughly opposite sides of the Earth. However, as the paleogeographical data got better it turns out they were pretty far off from being antipodal (about 5,000KM) Aren’t there vulnerable points at the 1/3 and 2/3 positions? ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [October 4, 2015, 12:28am UTC](https://boards.straightdope.com/t/dinosaur-extinction-hot-or-cold/733391/12 "2015-10-04T00:28:31Z")
> [@Colibri](#): > > Mammals at the time were mostly small and nocturnal. They probably often lived in burrows where they would have been shielded from the worst effects. They probably fed on insects, worms, and maybe seeds, which would have still been available after the catastrophe. > > Freshwater animals, including ones up to the size of crocodiles, also survived pretty well, again probably because their habitat provided some protection. Of course, a number of smaller types of dinosaurs also survived the extinction event, probably for roughly the same kind of reasons.