Britannica Library. CIA - The World Factbook. BioDigital Human: Anatomy and Health Conditions in Interactive 3D. Zientzia eta Teknologiaren Hiztegi Entziklopedikoa. JSTOR. Britannica Online Encyclopedia. Encyclopedia of World Biography. Human Anatomy Atlas. “How does evolution happen? Through a gradual process called selection. Individuals that are better equipped to survive and reproduce pass those traits to their offspring. These “selected” changes accumulate over thousands of years. We tend to think of natural selection—”survival of the fittest”—but sexual selection works the same way and can be just as strong in shaping how species look and act”. (From birdsofparadiseproject.org) The birds-of-paradise are among the most beautiful creatures on earth—and an extraordinary example of evolutionary adaptation.
Repasa y comprueba lo que sabes sobre el aparato respiratorio de los mamíferos (en este caso del ser humano): (Picture from Wikipedia) Revise the respiratory system (Check the process where air travels in and out of the body, in this web by BBC). Activity on The respiratory system (Check the process where air travels in and out of the body. Test yourself on the respiratory system. List of online encyclopedias. List of historical encyclopedias. List of encyclopedias by language.