Juncos: Adaptations and Behaviors

The video explores the rapid adaptation of juncos at UCSD compared to those on Mount Laguna. It highlights changes in breeding season, behavior, and physical traits due to urban environments. The study investigates whether these changes are genetic or environmental through common garden experiments, revealing significant genetic divergence in less than 30 years.

What is the main difference in the breeding season of juncos between Mount Laguna and UCSD?

• Juncos at UCSD start nesting earlier and have more broods.

• Juncos at Mount Laguna raise up to four broods.

• Juncos at UCSD breed only in May.

• Juncos at Mount Laguna start nesting in February.

How have male juncos at UCSD adapted in terms of aggression?

• They chase after mates more frequently.

• They have more black in their heads.

• They have less white in their tails.

• They have become more aggressive.

What physical trait is reduced in both male and female UCSD juncos?

• Wing span

• Beak size

• White in their tails

• Tail length

What is one of the cascading effects of the longer breeding season at UCSD?

• Females become more aggressive.

• Juncos migrate more frequently.

• Males are more interested in raising young.

• Increased aggression in males.

What trait is observed in UCSD juncos that allows them to cope with urban environments?

• Increased shyness.

• Decreased willingness to explore.

• Lower stress hormone levels.

• Higher stress hormone levels.

How do UCSD juncos differ in their communication compared to those on Mount Laguna?

• They do not sing at all.

• They sing at a higher pitch.

• They sing at a lower pitch.

• They sing the same as Mount Laguna juncos.

What is a significant behavioral change observed in UCSD juncos?

• They are more aggressive towards each other.

• They allow people to approach much closer.

• They avoid human interaction.

• They are less willing to explore new environments.

What is the purpose of a common garden experiment?

• To increase the number of broods juncos can raise.

• To study the diet of juncos.

• To determine if differences are genetic or environmental.

• To observe juncos in their natural habitat.

What did the common garden experiment reveal about the juncos' traits?

• All differences disappeared.

• Differences were solely due to environment.

• Many differences persisted, indicating genetic divergence.

• Juncos from both locations became identical.

What was a key finding from the genetic analyses of UCSD juncos?

• They have not evolved at all.

• They are identical to Mount Laguna juncos.

• They have more genetic similarities with other species.

• They evolved rapidly over less than 30 years.