The oldest fossils are located in the bottom layer.
Explain one way that scientists date (age) fossils.
One way scientists find out the age of fossils is when the fossils contain sedimentary rocks that give clues about the age of the rocks, also fossilized rocks must have lived during the same time as the rock was formed.
Wrhy are fossils sometimes out of order?
Fossils are sometimes out of order because the movement of the tectonic plates, which means the whole set of layers can get turned around . Rock layers can get bent, even folded too. Because of that the youngest layer may not be on the top.
On the left is an Ancient Crocodile, on the right is a modern crocodile.
Find one feature (trait) that BOTH fossils have in common.
One trait that both fossils have in common is they have long tails.
Explain what the trait is and what you think the trait was used for.
I think the long tails were used to hurt the prey by the crocodiles wiping their tail at them.
Based on these similarities, what can you conclude about these animals history?
Yes I think they're related even though the modern crocodile looks smaller, the snout looks shorter, and the head looks wider. The ancient crocodile's body looks longer, it's snout looks longer, and it looks skinny. They could have evolved and mutated on how they look today and even though their are some things that are different, they have the same traits and the Ancient Crocodile could have mutated to the crocodile that looks like today.
Do you think they have a resent (1,000,000 years ago) common ancestor or do you think their common ancestor is older than that? Why do you think that?
I think they do have a common ancestor because the Ancient Crocodile had to evolve. Just like I think the Ancient Crocodile evolved to the Modern Crocodile.
On the top left there is a human embryo, the top right there is a elephant embryo, bottom left there is a dog embryo, bottom right there is a mouse embryo.
What similarities do the embryos have?
The similarities the embryos have is the human, and dog head shape looks similar. The human, dog, mouse, embryos hands are in the same position also their hands and feet look the same. The elephant, and dog's eyes look the same colorwise. The human and the mouse embryos have red spots on their body's. The human embryo and mouse embryo both have tails.
What differences do the embryos have?
The differences the embryos has is the the human embryos head is bigger than the others. You can see that the dog embryos ears look already formed, the rest don't. The mouse embryo's eyes are white in the middle, and black around, the others' eyes are blue or red. The elephant isn't in the same position as the other embryo, like the other embryos hands, feet, and head are closely together.
Which two embryos are the most closely related? Why do you think that?
I think the Mouse, and the human embryo are closely related. They both have a tail, they have red spots on them, their head shape is similar, their hands and feet looks the same, they are in the same position. I think they are closely related because they have similarities in traits and the way their positioned.
Do you think they have a recent (1,000,000 years ago) common ancestor, or do you think their common ancestor is older than that? Why do you think that?
Yes I do think they have a common ancestor, because they had needed to evolve, mutat, survive, and reproduce, in order for their species to be a live.