In a lush, past landscape, a hungry Triceratops indulges in low-lying ferns and conical plant plants to power its 10-tonne framework. The animal swallows huge mouthfuls of roughage, seeds and all, before heading away in search of new feeding grounds.
Days later and miles away, the Triceratops empties its intestines and sows the seeds of the plants it ate, complete with fertilizer, in more overgrown soil than could be achieved without it.
The distribution of plant seeds in the bodies of animals, known as the zoo, is so common in modern ecosystems that plants often adapt their fruits and flowers to specific carriers. Fossils from the shit and the gut contents indicate that plant seed also hooked rides in dinosaur belly, although it is unclear whether these ratios were as widespread and sophisticated as they are today.
George Perry, a forest ecologist at the University of Auckland who studies the human pressure on seed dispersal, reflected on this topic during the coronavirus outbreaks on New Zealand.
“I know from modern ecosystems that large animals are important seed distributors,” said Dr. Perry said. “I thought, I have all the pieces: what is the most massive animal ever and how far could that seed have moved?”
In a study published Wednesday in Biology Letters, dr. Perry set out a framework for calculating how far dinosaurs – ranging in weight from about 20 pounds to 90 tons – could carry the seeds of prehistoric plants. He found that dinosaurs such as Triceratops or Stegosaurus had the right mix of size and speed to set off seed between three and 20 miles from parent plants. It is comparable to the African forest elephant, which carries an average of one and a half miles of seed, but can move up to 40 miles.
Dr. Perry’s simulations depend on two main factors: the speed of a dinosaur and the amount of time it takes seed before it is eliminated. It is difficult to determine these values due to the limitations of the fossil record. That said, body mass is linked to walking speed and seed retention time in modern animals, which can be used as a rough analogue to previous ecosystems.
“What we really want to be able to do is get a GPS tracker and put it on a dinosaur and track it, but we can’t do that,” he said. Perry said. For this reason, the assumptions of the study are ‘fairly conservative’, he added.
Large animals usually travel further and keep seeds longer compared to smaller animals. But extremely massive dinosaurs, such as the 90-ton Argentinosaurus, were perhaps slower than medium-sized herbivores. This means that refusers like Triceratops were probably the most effective seed distributors because of their modest body size, yet wonderful appetite.
“The distribution of the seed’s potential of extinct animals is of great importance, and Dr. Perry estimates that of dinosaurs in a meaningful way,” said Tetsuro Yoshikawa, a plant ecologist at the National Institute for Environmental Studies in Japan. published on this topic, said.
“Since existing terrestrial animals, such as elephants and bears, can transport seeds in some cases, it is possible that large dinosaurs have similar potential.”
Dr. Perry’s study is “an excellent example of how a scientist with clever lateral thinking can create ways to gain insight into a question that – at face value – can only be answered with a time machine,” said John Hall, a plant ecologist at the University of Queensland and an expert on cycad plants.
Of course, it would be great if scientists could immerse the elbow deep in real dino-mist, à la Ellie Sattler in ‘Jurassic Park’. Unfortunately, the finer details of these complex ecosystems are likely to be shrouded in mystery and speculation.
“When we look at the natural world of today, the diversity and intimacy of the close symbiotic relationships between plants and animals that pollinate flowers and spread seeds is just staggering,” said Dr. Hall said.
“There is no reason not to think that the spectrum of such relationships in prehistoric times should have been equally complex and diverse,” he added, even if “those relationships should be tediously lost to us.”