In a lush, bygone panorama, a hungry Triceratops munches on low-lying ferns and cone-bearing cycad vegetation to energy its 10-ton body. The animal swallows large mouthfuls of roughage, seeds and all, earlier than ambling off in the hunt for new feeding grounds.
Days later and miles away, the Triceratops empties its bowels, sowing the seeds of the vegetation it ate, full with fertilizer, in additional far-flung soil than could possibly be reached with out it.
The dispersal of plant seeds inside the our bodies of animals, often known as zoochory, is so frequent in fashionable ecosystems that vegetation typically tailor their fruits and flowers to enchantment to particular carriers. Fossils of poop and intestine contents point out that plant seeds additionally hitched rides in dinosaur bellies, although it’s unclear if these relationships had been as widespread and complex as they’re right now.
George Perry, a forest ecologist on the University of Auckland who research human pressures on seed dispersal, acquired to occupied with this matter throughout New Zealand’s coronavirus lockdowns.
“I know from modern ecosystems that large animals are important seed dispersers,” Dr. Perry mentioned. “I thought, I’ve got all the pieces: What’s the most massive animal ever and how far might it have moved seeds?”
In a examine revealed Wednesday in Biology Letters, Dr. Perry laid out a framework for calculating how far dinosaurs — ranging in weight from roughly 20 kilos to 90 tons — might need carried the seeds of prehistoric vegetation. He discovered that dinosaurs reminiscent of Triceratops or Stegosaurus had the right combination of dimension and velocity to deposit seeds between three and 20 miles from father or mother vegetation. That’s akin to the African bush elephant, which transports seeds throughout a mile and a half on common, however can transfer them so far as 40 miles.
Dr. Perry’s simulations rely on two foremost elements: the velocity of a dinosaur and the period of time it retains seeds earlier than eliminating them. It’s difficult to pin down these values due to the restrictions of the fossil file. That mentioned, physique mass is linked to strolling velocity and seed retention time in fashionable animals, which can be utilized as a tough analog for previous ecosystems.
“What we really want to be able to do is get a GPS tracker and put it on a dinosaur and follow it around, but we can’t do that,” Dr. Perry mentioned. For this motive, the examine’s assumptions are “reasonably conservative,” he added.
Large animals usually journey farther, and retain seeds longer, in contrast with smaller animals. But extraordinarily huge dinosaurs, such because the 90-ton Argentinosaurus, could have been slower than midsize herbivores. That means grazers like Triceratops had been most likely the best dispersers of seeds due to their extra modest physique sizes but nonetheless prodigious appetites.
“Seed dispersal potentials of extinct animals are of great importance, and Dr. Perry estimated those of dinosaurs in a sensible way,” mentioned Tetsuro Yoshikawa, a plant ecologist on the National Institute for Environmental Studies in Japan who has revealed analysis on this matter.
“Since extant terrestrial animals, such as elephants and bears, can transport seeds several kilometers in some cases, it is possible for large-sized dinosaurs to have similar potentials.”
Dr. Perry’s examine is “a great example of how with clever lateral thinking, a scientist can come up with ways of getting insight into a question that — at face value — could only be answered with a time machine,” mentioned John Hall, a plant ecologist on the University of Queensland and an professional on cycad vegetation.
Of course, it will be great if scientists may plunge elbow deep into actual dino dung, à la Ellie Sattler in “Jurassic Park.” Alas, the finer particulars of those complicated ecosystems will almost certainly stay shrouded in thriller and hypothesis.
“When we look at the natural world today, the diversity and intimacy of the close symbiotic relationships between plants and animals that pollinate flowers and disperse seeds is just staggering,” Dr. Hall mentioned.
There is “no reason not to think that the spectrum of such relationships must have been equally complex and diverse in prehistoric times,” he added, even when “those relationships must remain tantalizingly lost to us.”