What is the ultimate source of all new genetic variation?

Reciprocal altruism requires

The figure below compares Neanderthal skulls (orange box) with modern human skulls (blue box). What differences do you see?

Sympatric speciation occurs when two populations

There is no increased risk of choking when babies sleep on their backs.

Babies of mothers who smoked during pregnancy are at a higher risk of SIDS.

SIDS is caused by suffocation.

Nationally, 20% of SIDS deaths happened while the baby was in the care of a child care provider or relative.

6. Reflexión. Write a paragraph about the following topic (100-150 words approx.) ¿Crees que enfrentar y superar (to overcome) un reto o un desafío puede definir quiénes somos y en qué creemos más que otras experiencias?  Explica por qué o por qué no e incluye por lo menos un ejemplo de uno de los textos que hemos estudiado y discutido en esta unidad para apoyar (to support) tu opinión, además de usar ejemplos de tu propia experiencia.     En caso de que las necesiten (copiar y pegar): á é í ó ú  ÁÉÍÓÚ   ñ ¿? ¡ !

5. In the vocabulary for both the texto in Contraseña (where we read about Francisco’s experiences his first day at the university) and in the texto adicional (the video where Carina shares challenges she and her family faced when her son was diagnosed with autism) we found many words with positive connotations and many with negative connotations. Pick the 5 words or phrases from the list below that generally have a NEGATIVE connotation.