tag:blogger.com,1999:blog-8161161431451849208.post1194692959964485718..comments2024-03-28T02:45:03.204-07:00Comments on Antediluvian Salad: Hungry, Hungry BrontoDuane Nashhttp://www.blogger.com/profile/14467779935085970909noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-8161161431451849208.post-9105629032018247822013-01-20T13:18:01.601-08:002013-01-20T13:18:01.601-08:00Thanks for comment heteromeles!!!
Although I have...Thanks for comment heteromeles!!!<br /><br />Although I have used arguments involving island endemicism in the past the main thrust of my argument here is that I see no evidence that sauropods were any more, and in fact may have been less, stressful on vegetative communities than modern African elephants. For me we should consider both options- were sauropods massive tree killers, habitat modifiers and brush clearers on a scale unsurpassed in modern ecosystems? or were they in fact "softer" on the vegetation than generally assumed? I argue the latter and provide arguments in favor of my view. <br /><br />Just because sauropods were absolutely larger than elephants does not prove, imo, that they were absolutely more destructive than elephants. <br /><br />I am well aware that it gets a bit tricky in trying to infer past plant/herbivore relationships based on extant plants. And yes many conifers can "stump-sprout" and regrow from knarled conditions- but this may be due to surviving fires, landslides, and competition from other trees in the canopy, wind fall etc etc.- we don't have to automatically invoke sauropods. It is interesting to me that many cycads, tree ferns and palms (pretty common in Cretaceous) will out right die once their growing tip is severed. I do not see why, even after 65 million years of evolution, that these plants would ever lose the ability to regrow from chomped growth tips if they ever even had the ability to begin with. Even if mammalian herbivores generally do not target these plants to eat, the ability to resprout from damaged tips proves useful in many instances such as fire, natural breakage, insect damage. I just don't see why that ability would be lost unless it was never there to begin with.<br /><br />Again thanks for the comments!!Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-74719301026357047692013-01-20T08:52:01.978-08:002013-01-20T08:52:01.978-08:00There's a critical mistake here: plants adapt ...There's a critical mistake here: plants adapt *FAST* to the lack of herbivory. This is a classic problem with island plants. They shed defenses and invest more in growth, but that makes them exquisitely vulnerable to introduced herbivores. This happens at the scale of thousands to millions of years.<br /><br />Modern conifers have not dealt with non-avian dinosaurs for the last 65 million years, and it's silly to assume that they stopped evolving at the KT boundary.<br /><br />We can see some relicts of anti-sauropod defenses in things like redwoods' ability to readily regrow, the rather interesting toxins of cycads and ferns. Still, I seriously doubt we're seeing the whole panoply of tricks they used against dinosaur browsing. <br /><br />The other thing to remember is that the trick for plants isn't to repel all herbivores, it's to better survive herbivory than your neighbors do. This is the trick that grasses use to take over the world. This strategy only works when herbivores are a major force. Get rid of them, and every plant that uses this strategy gets overshadowed by those that don't. That undoubtedly happened after the K-T.<br /><br />Anonymousnoreply@blogger.com