* Biologist: Studies living organisms and their interactions with their environment.

* Microbiologist: Studies microorganisms, such as bacteria, viruses, and fungi.

* Zoologist: Studies animals.

* Botanist: Studies plants.

* Ecologist: Studies the interactions between living organisms and their environment.

Physical science

* Physicist: Studies the properties of matter and energy.

* Chemist: Studies the properties of chemicals and their interactions.

* Astronomer: Studies the universe.

* Geologist: Studies the Earth's surface and interior.

* Oceanographer: Studies the oceans.

Earth science

* Meteorologist: Studies the atmosphere and weather.

* Climatologist: Studies climate.

* Hydrologist: Studies water.

* Geographer: Studies the Earth's surface.

* Paleontologist: Studies fossils.