A Dimetrodon amongst Alethopteris ferns.

Dimetrodon was the apex predator of its time. They came as large as 11 feet long, 4 feet tall, and weighing as much as 300 pounds. Their reptilian hide, a relative novelty for that period, ensured their survival out of water. The large sail may have helped them to regulate body temperature, a survival advantage during the extremes of hot and cold during the Early Permian. . . Alethopteris was a seed fern that populated much of the world during the Carboniferous and Early Permian periods. Long extinct, fossilized leaves from the Alethopteris are commonly found today.

AL AIRE LIBRE • ANIMAL • ANIMAL, UN • BESTIA • CARNIVORO • CIEMPIES • CIENCIA • CIENCIAS NATURALES • CREATURE • CRIATURA • DENTADURA • DEPREDADOR • DÍA • DIENTE • DIENTES • DIENTES, LOS • DUREZA • EPOCA PREHISTORICA • ESPECIES • EVOLUCION • EXTINGUIDO • FEROZ • FLORA • GARRA • GEOLOGIA • HISTORIA NATURAL • HORIZONTAL • ILUSTRACION • IMAGEN EN COLOR • IMAGEN GENERADA DIGITALMENTE • MUELA • NATURALEZA • OUTSIDE • PALEONTOLOGIA • PASADO • PELLEJO • PLANTA • PRIMITIVA • PRIMITIVO • REPTIL • SIN GENTE • TEMAS DE ANIMALES • VEGETACIÓN • VERTEBRADO • VIDA SALVAJE • ZOOLOGIA