Comment by dluan
8 years ago
Last week I was in the field digging dinosaurs in Montana, when one of the dig leaders mentioned there was no grass back then, just lots of ferns, because grass hadn't evolved yet.
It kind of blew my mind that for most of dinosaurs, there was just a lot of leafs and ferns.
Here's some pictures for context (https://imgur.com/a/rE5wwc4), when you're out where most dino bones are found, you forget that it may have been a lush landscape of riverbeds approaching the ocean coastline, or that it may have been a dry arid desert landscape like in the land before time movies. Regardless, it's odd to imagine all of it, with no grass.
400 million years ago, there were no trees. But there were giant mushroom forests https://www.smithsonianmag.com/smart-news/long-before-trees-...
Can anyone just dig? I’d love to join the journey for a week or two.
Not only that, but grass has a special kind of photosynthesis that can survive in a lower CO2 atmosphere than other kinds of plants. Believe it or not, one of the long term hazards for life is too little CO2 for photosynthesis, below 100 ppm. The long term driver of CO2 is geology: weathering of rocks and formation of limestone in the deep ocean remove CO2; subduction zone volcanos return it to the atmosphere. Biosphere carbon is less than one percent of geologic carbon. When the Earth cools down too much to continue plate tectonics in a billion years or so, there will be too little volcanic carbon returned to the atmosphere. Plants and algae will die and so will all animals that eat them. Only chemeotrophic microbes will remain.
Sentient life could halt this process by burning limestone to release carbon. This is how cement is made.
Do you have a blog post with more photos/context? It can be an interesting submission, specially if you can answer the comments.
Lots of mosses though? I imagine more primitive vegetation filled that role.
Dunno! I think most larger dinosaurs then needed larger sources of energy. Look at the teeth of an ankylosaur or most ceratopsians - they're designed to chomp and scissor through large leafy kale.
Adapted, not designed.
There wasn't even grass in South Africa until humans brought it there. Surprised me too.
Really? It doesn't seem to be true: http://rstb.royalsocietypublishing.org/content/371/1696/2015... talks about grasslands in South Africa 1-2 million years ago, well before humans existed.
OK, it seems I misunderstood because I don't know much about grass. It seems there was some grass there a long time ago, but there is also a lot of "alien grass" that was introduced to the Cape region by humans. The alien grass is considered invasive and outcompetes the natural vegetation there which is called fynbos.