Adaptations in Redback Spiders Flashcards
The pollen from a 4n (68 chromosomes) plant is crossed with the ovum from a 2n plant (34 chromosomes). What would be the chromosome number in the offspring?
51 chromosomes
What is the region where members of different species mate and produce hybrids?
hybrid zones
How might hybridization impact speciation?
Reinforcement of reproductive barriers
What is fitness?
How many viable, fertile offspring an individual (or allele) leaves in subsequent generations relative to others in the population
What is an adaptation?
Trait or behaviour that makes an organism better suited for its environment
What is sexual cannibalism?
When one sex consumes the other during sexual reproduction
What is the mistaken prey hypothesis? If this hypothesis is correct, what would you predict?
Females mistake males for prey. If this hypothesis was correct, females would sometimes attack males as soon as they enter her web.
What is the mate rejection hypothesis? What would you predict?
Females eat males that are unsuitable as mates. The prediction would be cannibalized males would be smaller and produce fewer offspring that non-cannibalized males.
What is the hungry lover hypothesis? What would you predict?
Females eat their mates because they are hungry. The prediction would be females would be more likely to cannibalize males if their diet has not been supplemented.
Of the three hypothesis for the sexual cannibalism of the redback spiders, which one was found to be true?
They hungry lover hypothesis.
How does the female consume the male spider?
He dangles hid abdomen in front of her jaws
Why does the female redback spider consume the male?
The female gains nutrients if she eats the male
What is the paternal investment hypothesis?
Males by contributing nutrients to increase the number and size of their offspring.
If the paternal investment hypothesis is correct, what would you expect?
Consuming he male would significantly increase the number and mass of eggs in the female’s egg sac.
What is the nuptial gift hypothesis?
Males benefit from self-sacrifice by increasing their fertilization success
