The beginning of the Cambrian Period is marked by the evolution of hard body parts such as calcium carbonate shells. ... These body parts fossilize more easily than soft tissues, and thus the fossil record becomes much more complete after their appearance.
Answer: All birds are warmblooded, or endothermic, animals. Birds are vertebrates because
they have backbones. All birds have a four-chambered heart, a
characteristic they share with mammals. All birds lay hardshelled eggs. Birds have only two legs. Their forelimbs have
become modified into wings for flying. All modern birds evolved
from ancestors that could fly.
Explanation:
Answer:Several theories have been proposed for the formation of desert pavements. A common theory suggests they form through the gradual removal of sand, dust and other fine-grained material by the wind and intermittent rain, leaving the larger fragments behind.
Explanation: scientists have had sever theories as stated in my answer above
Answer:
The process that Mildred used is known as Radiocarbon dating
Note: The question is incomplete. The complete question is given below:
Mildred collects a sample of fossilized plant material. She takes it back to her lab to run some tests on it. Mildred is able to measure the amount of carbon-14 in her sample and compare this to the amount of carbon-12 in it. She uses this information to calculate that the fossil is 4,500 year old. The process that Mildred used is known as _______
Radiocarbon dating
Faulting
Indexing
Superposition
Explanation:
Radiocarbon dating is a process of determining the age estimates of various objects and materials using the radioactive properties of an isotope of carbon, carbon-14.
Radiocarbon dating uses the ratio of two isotopes of carbon, carbon-12 and carbon-14 present in materials which contains carbon to determine their age.
There is a fairly constant ratio of carbon-12 and carbon-14 in living organisms. However, at death, due to the decay of carbon-14 to carbon-12, the ratio begins to change. Since the rate of decay of carbon-14 is fairly constant, a property known as half-life, the time it has taken for carbon-14 to decay to carbon-12 can be calculated. This calculated time will givee the age of the fossilised material.