Why do scientists think that the first true cells were probably anaerobic?

Anaerobic because there was little oxygen; and

heterotrophic because autotrophism (the ability to manufacture your own food) is a more complex process ... the first cells would have derived energy from surrounding organic molecules, which makes them heterotrophic.

Anaerobic because there was little oxygen; and

heterotrophic because autotrophism (the ability to manufacture your own food) is a more complex process ... the first cells would have derived energy from surrounding organic molecules, which makes them heterotrophic.