It's called an index fossil.
A long span of geologic time is called an era. This is a major division of geologic time that is further subdivided into periods. Examples of eras include the Paleozoic, Mesozoic, and Cenozoic.
A gap in an area's geologic history is called an unconformity. This represents a period of time where rock layers are missing due to erosion or non-deposition. Unconformities can help geologists understand the timing and duration of geological events.
A contact or boundary.
The natural environment of a living organism is called its habitat. This includes the specific location where an organism lives and interacts with other living and non-living components of its surroundings. The habitat provides the necessary resources for the organism to survive and thrive.
An inherited characteristic that increases an organism's ability to survive and reproduce in its specific environment is called an adaptation. Adaptations help organisms better suit their environment and increase their chances of survival and reproduction.
The term for the specific combination of alleles an organism has is called its genotype.
The presence of urease indicates the presence of a specific bacteria called proteus. It's useful to identify the organism to determine the correct antibiotic to cure it.
A phenotype
The key that helps identify organisms is called a taxonomic key. It is a tool used by biologists to classify and identify organisms based on specific characteristics such as physical traits, habitat, and behavior. Taxonomic keys typically consist of a series of yes or no questions that lead to the correct classification of the organism.
A niche is the specific area where an organism inhabits.
Criteria
specialization
Pheromones.
Criteria
Geologic Time. It's called the Geologic Time Scale.
The specific type of environment in which an organism lives is called its habitat. This includes the physical and biological factors that make up that particular place and meet the organism's needs for survival and reproduction.
An organism that has genes that are alike for a particular trait is called homozygous for that trait. This means that it has two identical alleles for that specific gene.