Mini Thresholds
Photosynthesis
Photosynthesis first happened about 3.5 billion years ago, when some prokaryotic cells developed the ability to harvest light as an energy source for metabolism. This gave living things access to a huge new source of energy - sunlight. But it also released oxygen into the atmosphere, which was toxic to many of the existing life-forms. New forms of life were able to adapt to the oxygen in the atmosphere. If this threshold had not happened, my species, the alligator snapping turtle, would not exist. Its food are part of a food chain that starts with photosynthesis by water plants and algae.
The first type of lifeforms were prokaryotic, but after 1 million years a new cell called eukaryotes which is what most species' cells are.
Eukaryotes
It happened 2.5 billion years ago it formed a new kinds of cell that most creature use. It also developed the ability to have organelles inside cells that performed special functions and lock DNA cells in the nucleus. This made new cells which help make plants, animals, and fungi. More food to eat along with land to live in. If this didn’t happened my creature the alligator snapping turtle would not exist. Mostly every creature has eukaryotes in its body including the alligator snapping turtle. Besides that there are animals with these cells that the turtle eats.
Multicellular Organisms
This thing made cells cooperate to form more complex life forms with new bodies along with cells working with DNA. It happened 1 billion years ago. With this there came sexual reproduction which some animals that the turtle uses along with eating other animals that use this process as well. Without this threshold there would be no alligator snapping turtle. This threshold help made new land and species including the alligator snapping turtle also the speies eat other species that are multicellular organism.
Brains
Brains happen 540 million years ago it coordinated activities of different parts. Brains helped species become more complex and helped them think. They were able to hunt, hide, defend, and attack better. Without brains the alligator snapping turtle wouldn’t exist. Brains helped it survive because the turtle uses its brains to hunt to get food, lay eggs and hide them away from predators, defend themselves against other species, and attach when needed to. Then make the turtle do more complex things.
A Brain of a Turtle
Ocean to Land
This threshold happened 475 million years ago species needed to create more skins and breathe in and out in a new way also plants and fungi came first. With this threshold it created fungi and plants which animals use to hide, live, and eat. Also during this time reptiles were starting to pop up. If this threshold never happened the alligator snapping turtle wouldn’t exist. One of the first species that left the ocean were a type of reptiles which the alligator snapping turtle are. With no animals leaving the ocean there would be no alligator snapping turtle, places for it to live, other species to eat, and etc.
Reptiles were one of the first species on land so here is a picture of them on the tree of life
Mammals
This threshold happened 250 million years ago where new warm-blooded, furry, non-laying egg, and four-limbed animals. They also were a new parenteral that were called ernobyros that develop in the mother and drink the mother’s milk. After million a years after the dinosaurs died off mammals besides bacteria were the world’s population. Humans are mammals and have taken over most of the world. Even if the alligator snapping turtle is not a mammal, but a reptile its prey is some small mammals. Though if there was no mammals which are the alligator snapping turtle’s only main threat and has caused it to be threaten to extinction. Also it doesn’t eat all mammals it also eats fish, frogs, toads, and other turtles. It could be a win-win solution.