Rewardless Orchids (D. sambucina)

Question 1

Which species does this paper look at?

Answer 1

The rewardless orchid Dactylorhiza sambucina

Question 2

The orchid shows a stable and dramatic flower-colour …, with both … and … flowered individuals present in populations throughout …

Answer 2

polymorphism, yellow, purple, Europe

Question 3

What does rewardless mean?

Answer 3

They are flowers but don’t produce a reward for their pollinators, either through nectar or pollen

Question 4

Who is this study carried out by?

Answer 4

Gigord et al. (2001)

Question 5

The study showed clear evidence that … colour morphs have … advantage through male and female components

Answer 5

rare, reproductive

Question 6

This is the first demonstration that … …-… … through pollinator preference for rare morphs can cause the … of flower-colour morph polymorphism

Answer 6

negative frequency-dependent selection, maintenance

Question 7

Flower colour is diverse through flowering plants, but variation within a species is …. Most of these polymorphisms cover a small colour … and may simply be due to … …

Answer 7

uncommon, ranges, phenotypic plasticity

Question 8

Species that show a true, …, … based polymorphism are comparatively …

Answer 8

stable, genetically, rare

Question 9

… often show this

Answer 9

orchids

Question 10

Rewardless orchids are usually pollinated by newly … … insects (typically bumblebees)

Answer 10

emerged, naive

Question 11

Bees tend to sample different colour morphs in alternation (shown as visiting an … flower increases the probability of switching to a … colour morph). This behaviour results in … morphs being proportionally …

Answer 11

empty, different, rare, over-visited

Question 12

This means that in orchids, in order to pollinate effectively without a reward, it is beneficial to have a rare colour morph. The relative … of a morph is predicted to … as its relative frequency …. This is a mechanism for maintaining the different colour morphs.

Answer 12

fitness, decrease, increases

Question 13

The mechanism predicts a frequency where each morph has an equal …

Answer 13

fitness

Question 14

The study found that…

Answer 14

relative male and female reproductive success of the morphs was significantly negatively correlated with morph frequency across experimental arrays.

Question 15

At both extreme frequencies, the … morph has a significantly higher value for reproductive success, compared with the … morph

Answer 15

common

Question 16

This shows negative frequency-dependent selection, mediated by … … …, which is a mechanism more maintaining the colour morph polymorphism

Answer 16

pollinator foraging preference

Question 17

There was a bias towards yellow flowers, which can be explained by…

Answer 17

innate pollinator preferences to certain flower colours (shown experimentally previous)