Is that really a universal, or does it apply mainly to mammals? Just how warm-blooded the dinosaurs were is still debated, and cold-blooded animals don’t require as many units of food to make one unit of critter as do warm-blooded creatures.
Snakes hold the record for % of their body weight consumed at about 30%. And this meal can last them 6+ months, though they’d be willing to eat in as little as a month or two.
On the other hand, a lion can only handle about 10% of its body weight.
So… I’ll stand by 5 or 6 humans in a single meal as the likely maximum for a T-Rex. Perhaps it could gorge itself on a few more, but would it? A lion gorges itself because it’s made a single large kill and anything it doesn’t eat goes to waste. Humans are not a single large kill for a T-Rex.
Life density can’t exceed what plants can provide, regardless of what humans do.
A predator like a lion has a 100-square mile territory. They’ll fight off other lions to maintain that territory, so it’s not like humans are affecting this size very much. We don’t know whether T-Rex was territorial, but they eat too much to be densely packed.
And, yes, humans are top predators and have a huge impact on other life, especially large animals. That’s actually my whole point. We beat lions and tigers and bears. Bring on the dinos!
That is an upper estimate used by some scientists. 25 mph seems to me a much more reasonable top speed. There are others who say that it was closer to 11 mph.
In any event, this is not so different from other prey and predator species that humans have had to contend with. Lions can hit 50 mph.
What if there are only 5 people in your time party?
Bad planning. Regs say that ten is an acceptable minimum, though admittedly that’s only a guideline.
Incidentally, all members of your party should wear the same style of outfit. International Safety Orange outerwear is recommended, as most dinosaurs are believed to be colourblind. Rumours that the popular red tunics make party members more visible to carnosaurs are false.
All I am saying is that if I am on this mission, it is probably wise to not wear the red tunic.
As to the OP, I doubt the T-Rex and co. are going to be the most dangerous to you. I suspect the danger comes from pack hunters, if they existed, think of a wolfpack of these…
http://en.wikipedia.org/wiki/Utahraptor
http://commons.wikimedia.org/wiki/File:Baltow_JuraPark_utahraptor_ostrommaysorum_01.jpg
The last pic is a little over the top
Capt
Missed edit window
I think the some sort of camouflage is in order with safety orange as the reverse, in case they can see that color. I would also worry about “Human Smell” and the Saur’s olfactory senses.
Capt
I think as a species humans could take out the dinosaurs once they had them figured out … all indications are that they were not very bright, even for animals. That said, there would probably be quite a few casualties along the way.
First of all, it depends on whether the time travelers planned to go back to the time of the dinosaurs, or were transported to the wrong time, or transported against their will. When you plan to go back in time you bring automatic weapons, explosives, even RPGs with you. Your only problem is that in a surprise attack by a roving band of teenage raptors just as you land in the past, your time transponder necessary for your recovery is taken by a pterosaur to a distant location. So the party has to make it’s way across the Jurassic landscape to retrieve it. But the heavy weaponry keeps the predators at bay, for at least one of the travelers who make it back alive to the present time.
Now if they aren’t, then you have a different situation altogether. They don’t have any weapons. One of them might have a pack of matches or a lighter, maybe another one has a pocket knife, that’s about it. They are a snack pack waiting for a hungry T. Rex to drop by. But luckily one of them will be as smart as the Professor on Gilligan’s Island and he can construct a time machine from prehistoric coconuts. It will take a while, but in the mean time he’ll work with the member of the party who’s an ex-military man who will make pointy sticks to hold off the predators when they retreat to their conveniently located cave with an entrance just a little to narrow for the dinosaur to enter.
So either way you cut it, it’s going to be dangerous. But you could be dropped off anywhere. The great danger may be lack of food, or flooding from endless tropical storms, or the ancient tree shrew sized ancestors of mammals that come out at night. And you just as easily may be dropped off in a secluded glen ripe with edible vegetation and frequented only by dull witted ambling vegetarian dinosaurs. But aside from the dinosaurs, all the other dangers are present on the planet now, plus some we invented since then.
I thought it was more like 15mph. [1]
Regardless T rex has a reptilian/bird brain. Should I think of it as a crocodile or a snake with a huge jaw? It might lack maneuverability and sustained speed.
Here’s the scenario. One dozen briefed humans, each with an AK-47, 100 rounds of ammunition, a technological encyclopedia, camping gear, a school bus and a tank of gas. In other words, they can use the heavy artillery for a while, but eventually they will have to dig up the saltpeter on their own. I assume they would spend a few years at the spear and arrow stage. Would T rex et al be manageable? Or are they 20x worse than Kodiak bears?
[1] Wiki! “Scientists have produced a wide range of maximum speed estimates, mostly around 11 metres per second (40 km/h; 25 mph), but a few as low as 5–11 metres per second (18–40 km/h; 11–25 mph), and a few as high as 20 metres per second (72 km/h; 45 mph).”
Let’s say it’s 15 mph, but that there are pack animals to worry about as well. Humans can hide against huge creatures in heavily forested areas after all.
ETA: Eh, give each of our heroes a machete and ax as well.
I agree with the poster who said earlier that smaller carnivores that were basically pack animals like wolves would probably have been a lot more dangerous to humans, if only because they would be more numerous and more persistent. A human is not a big meal for a T-rex, it is for a Utahraptor. Fast moving bipedal crocodiles who hunt in packs and thus have the kind of intelligence implied by that, and which think humans are edible, are a scary prospect.
Really? That would be odd, given how many reptiles and just about all birds see color just fine. It’s mammals that are mostly colorblind.
Which is just an example of how our current world leaves us ill-equipped for a dinosaur world where the major predators aren’t mammals.
Given that scenario, any time in the last 10,000 years would be better than any other time in history.
As an aside, sorry for the hijack, during the carboniferous era (giant insects and ferns etc.), the O2 percentage in the atmosphere was higher, how might that have affected our potential Homo Sapiens visitors.
Yes I know it was some 300 million odd years ago so maybe the mods want to move this somewhere else?
Peter
There’s no reason to think that the Mesozoic era was like Kong Island, with every living thing berserkly out to kill you on sight. The main thing, as alluded to upthread, is that the predator/prey scale had an entire size range not matched in any other era of animal life. The largest mammalian carnivore probably never exceed one tonne, while theropods such as T. Rex were in the range of seven tonnes or more. So although a T. Rex might have eaten a human (about as often as lions bother to eat rabbits), the biggest danger would have been from second-tier predators like Utahraptor.
Agreed, smaller predators would have been a more serious problem. T rex is not going to *hunt *people, just eat them if they turn up.
The lion/rabbit analogy is good, but I was thinking more like a robin looking for worms. Random bugs aren’t safe in that situation.
But at any time before the end of the last ice age, humans would have been prey to anything big enough to eat them.
Lions, bears, sabertooth cats, things that we don’t even have names for , all would have cheerfully eaten humans.
You’re talking about a planned human attack against a large dinosaur. I’m talking about a hman defense against dinosaur predations.
I don’t see how it could be defended against. Any number of people, even armed with weapons, would be plowed through like toy soldiers, and I don’t see how people might have constructed a defensive barrier strong enough either.
Note this also applies to the large-individual-versus-small-pack discussion as well. People seem to be focusing on a lone human, but people could and presumably would band together themselves and successfully defend against packs of smaller animals. But that would not apply to a T-Rex.
Well, with a group you’d fall back on our basic assets- hands and fire.
Construct a kraal, with spikes pointing out all around. Build watch fires at 4 or 8 places, depending on the size.
Come daylight, an armed party sets out to find a cave, preferably on high ground. Moving the party there safely would be a challenge.
Really, Tunnel In the Sky is quite on topic. I may just break out my copy and reread it today.
You find natural barriers to colonize.
If it weren’t for the larger herbivores you could set up housing in the tree tops but the big 'saurs could clearly pose a threat not because they want to eat you but because they want to eat the tree you’re sheltering in or can knock it down (on a smaller scales, elephants will knock down trees to get at the munchie bits on top). So you’d want something made of rock. Look for a mesa that a human could climb up (you might need to modify it a bit to make a stairway/ladder) but a potential predator couldn’t, or at least would force a predator to come at you one at a time. Or a cave with a narrow entrance (to keep the biggest predators out) with a dry pit moat beyond it filled with large, sharp stakes. You’d still have to post guards for smaller pack-hunters and the equivalent of vermin but it should be manageable.
This, of course, presumes you will live long enough to find/build such a refuge.
Nearly every dinosaur panorama has a volcano spewing on the horizon. Sometimes more than one.
Ditto me as interested. Cite?