Plants Seed Dispersion - Assignment Example

What fruit or seed adaptations might plants have for dispersal using abiotic vectors such as wind?

Dispersal is the spreading of plants offspring’s to different locations where they are expected to grow into new plants. If they are not dispersed to many trees will grow at one point. They end up not surviving due to competition of resources. Flowering Plants use various ways to disperse commonly referred to as the dispersal vectors. They are either biotic or abiotic. The plants that use abiotic factors such as wind have adaptations to make the dispersal successful. Some of these adaptations include having single-seeded fruit, seeds have large wings attached on the side, and this enables them to spin as they fall.

2. What fruit or seed adaptations might plants have for dispersal using biotic vectors such as birds or small mammals?

Those that are dispersed by biotic factors such as the birds and small mammals have their adaptations too. These include having hooks to attach themselves to animal’s fur, and they also have attractive fruit pulp to attract birds and animals

3. The box in Figure 1 below represents a hypothetical forest with four adult trees of the same species, labelled A, B, C, and D. There may be more trees from other species around them, but those trees are not shown. Assume that these trees do not consistently affect wind direction.

a. If wind disperses the seeds of this species, what pattern of seed dispersal would you expect to observe for each tree? Draw multiple lowercase letters a–d to show where you expect seeds to land for each of these four individuals. (Note that you are drawing a seed shadow, the pattern of seed dispersal away from the parent plant.)

b. In the space next to the figure, explain why you made the prediction you did.

The seeds would disperse away from parent’s trees because they have wing and it’s difficult for them to fall immediately close.

The box in Figure 2 represents the same hypothetical forest. This time, however, imagine that the trees' seeds are dispersed by animals. a. What would the seed shadow look like if birds dispersed the seeds of the hypothetical tree species in Figure 2? Use multiple lowercase letters a–d to show the seed shadow you would expect for each of these four individuals. b. What would the seed shadow look like if monkeys dispersed the seeds of the hypothetical tree species in Figure 2? Use multiple uppercase letters A–D (in a different colour, if possible) to show the seed shadow you would expect for each of these four individuals. c. In the space next to the figure, explain why you made the predictions

Those dispersed by birds would fall far away from the tree than those dispersed by wind. Again those dispersed by monkeys would fall far much apart since monkey travel long distance. Still they are clumped together since they are from animal faces.

Describe the similarities and differences in the predicted seed shadows you drew for the wind-dispersed seeds (Figure 1) versus the bird-dispersed seeds (Figure 2).

Among the similarities between the two is they don't fall far away from the plant, and one of the differences is that those spread by birds cluster together while those of wind does not.

Imagine that the forest in Figure 2 gets bisected by a road that isolates the trees near tree “C” and creates two forest fragments. Describe the similarities and differences in how seeds dispersed by birds would be affected by forest fragmentation compared to seeds dispersed by spider monkeys.

The seeds dispersed by birds and monkeys would still fall far from the plant, but one difference is that those dispersed by monkeys will be interrupted since monkey requires uninterrupted canopy. Therefore this endangers dispersal by monkeys, unlike birds which will continue to fly regardless.

. As shown in the video Seed Dispersal and Forest Fragmentation, biologists have developed creative ways to use insects to help them find seeds that animals have dispersed. However, when these clues are not available, biologists use different approaches to investigate seed dispersal. What other tools or sources of information do you think biologists could use to study seed dispersal?

Other is many tools that researchers and use apart from the use of insects. They include use trapping devices to catch animals or birds.

Time to brainstorm ideas! a. How would you conduct a study to investigate seed dispersal by wind? I. State a research question you would investigate. ii. Describe the kinds of data you would need to answer the research question. iii. What experimental design would you use to study this quest?

This study would be conducted through an experimental approach in a certain forest. The research question would be how does wind affect seed dispersal? The data needed to answer this question is the amount of seeding that has been dispersed of a specific tree, the distance of these seedlings from the plant, the amount of germinated seedlings, the distance of those germinated seedlings.

The experimental design that I would use to investigate these questions would isolate various species of trees so that there is no confusion when gathering data. It would require finding tree species that are well spaced so that the seeds found would be that of the specific tree only.

How would you conduct a study to investigate seed dispersal by birds? I. State a research question you would investigate. ii. Describe the kinds of data you would need to answer the research question. iii. What experimental design would you use to study this question?

This study would require gathering data on the questions needed to answer and analyzing the data. The research question would be factors affecting seed disposal by birds. Some of the data to be collected would be the number of seeds dispersed by birds, amount of seeds that germinate and at what distance does it spread far away from tree. The experimental design would require to have a forest with multiple different species and collecting the faces from the area to know the dispersal rate.

What do the data in Figure 4 indicate about the survival of seedlings and saplings at different distances from the parental tree?

The survival rate is high since the seedlings are dispersed away from the parent tree, and they are not clustered together.

. Summarize the claim or claims the graph in Figure 5 is communicating

The graph from its representation clearly shows that not all seedlings that were dispersed in a certain area germinated and formed saplings. Again those seedlings dispersed far away from the mother tree had high chances of converting to saplings.

Considering Figures 4 and 5, summarize what the combination of seed, seedling, and sapling data tells you about seed dispersal by wind.

The data needed would be the proportion of seeds, the seedlings and saplings. Additionally, you need to know the maturity rate, and this is by dividing the number of seeds and saplings with seeds at every distance away from the tree.

12. What can you determine about the seed shadow for Focus cyrtophylla based on the data in Figure 7?

It is possible to tell that the high the proportion of seed the high the chance of survival. Additionally, sees that are far away from the mother tree have high chances of survival.

13. What do the results indicate about the survival of seedlings at different distances from the maternal tree?

The survival rate near the maternal tree is low, and as one moves away from the maternal tree, the survival rate increases.

Describe similarities in the seed shadows of the wind-dispersed and bird-dispersed tree species.

The similarity is the seeds that fall away from the maternal tree have a high chance of survival. Again those are in clusters have a low chance of survival, unlike those that are spacey dispersed.

. Describe differences in the seed shadows of the tree species with different dispersal vectors.

The difference is that those that are dispersed by birds have a high chance of survival than those dispersed by wind. Again the seeds dispersed by birds most of them fall far from the tree than those dispersed by wind.

16. How do the observed patterns compare to the predictions you drew in Figures 1 and

There is comparison since the seeds dispersed by birds are much more far from the maternal tree. Again those dispersed by wind form small clusters than those that are dispersed by animals.

17. Why do you think that the researchers studied not only seed dispersal distances but also the distances of seedlings?

This is because the distance of the seedlings is determined by the seeds distances. Again not all seeds convert to seedling, and it’s important to consider this element so as to know how the difference in distance affects the survival rate.

Estimate the range over which about 70% of the Platy podium seeds are likely to fall. Do the same for the Focus seeds.

Estimated Platy podium seed dispersal range (m) for about 70% of the seeds __these would disperse at the yellow region.

Estimated Ficus seed dispersal range (m) for about 70% of the seeds . These seeds would disperse close to the maternal tree—the red region.

. How does the distance that most seeds are moved compare to the distance where most seedlings establish?

The distance where more seeds are moved has fewer seedlings, and where there are more seedlings, there are fewer seeds.

21. What do you think causes this pattern? This because where seeds are clustered together, the survival rate is low because they are competing for resources. Those that are more dispersed don’t compete for

Resources.

The video Seed Dispersal and Forest Fragmentation describe seed dispersal by spider monkeys. In the introduction to this handout, you learned that small monkeys typically travel 100–400 m before depositing faeces that contain seeds from several different species. Birds often travel two to three times that distance before depositing seeds. Use this information and the data from the previous experiments to make a prediction in the form of a graph for where you would expect to find seeds and seedlings from a monkey dispersed fruit tree as a function of distance.

S

S

S

S

SS

ss

SS

MOTHER TREE

SSS

S

S

s

23. Can seeds from the individuals of the three different species disperse naturally to the conservation areas? Draw letters to indicate where you expect seeds from the nine indicated trees could disperse from the forest to the conservation areas.

The seeds would disperse, but there would be a limitation when it comes to monkeys. They would be interrupted by the canopy.

24. Suppose you have funds to be able to purchase seven additional 100 m × 100 m plots. Which seven would you purchase? Indicate them on the map. Why would you purchase those plots? How would they help achieve your conservation goal?

I would purchase them because they would repair the retarded areas, thus allowing more seeds to come in the area since monkeys will now have freedom of movement and will cover longer distances.

25. Is this hypothesis consistent with the results of the studies on Platypodium and Ficus? If so, how? If not, why not? Yes, it is consistent. This because from the various graphs eve had they show the same data. The longer the distance from the maternal tree, the high the chances of survival.

26. List possible mechanisms leading to this pattern. What leads to this is that those close to the maternal tree are likely to be affected by diseases and pathogens specific to those species.

27. Pick one mechanism from your list and describe how you could test whether the mechanism is causing the pattern.

I would pick diseases and sample an area where the seedlings are close to the maternal tree. I would find the level of damage the disease cause. I would then experiment far from the maternal tree and find seedling of the same species and examine the damage again caused by the diseases.

28. How might this mechanism support the diversity of pathogens, herbivores, biotic dispersers, and trees found in tropical forests?

It would support in that where several species are close they are attacked by diseases and pathogens than where they are mixed. Where they are mixed the pathogens don’t get enough food hence wouldn’t survive and neither would herbivores survive.

Describe the similarities and differences in the predicted seed shadows you drew for the wind-dispersed seeds (Figure 1) versus the bird-dispersed seeds (Figure 2).

Among the similarities between the two is they don't fall far away from the plant, and one of the differences is that those spread by birds cluster together while those of wind does not.

Imagine that the forest in Figure 2 gets bisected by a road that isolates the trees near tree “C” and creates two forest fragments. Describe the similarities and differences in how seeds dispersed by birds would be affected by forest fragmentation compared to seeds dispersed by spider monkeys.

The seeds dispersed by birds and monkeys would still fall far from the plant, but one difference is that those dispersed by monkeys will be interrupted since monkey requires uninterrupted canopy. Therefore this endangers dispersal by monkeys, unlike birds which will continue to fly regardless.

. As shown in the video Seed Dispersal and Forest Fragmentation, biologists have developed creative ways to use insects to help them find seeds that animals have dispersed. However, when these clues are not available, biologists use different approaches to investigate seed dispersal. What other tools or sources of information do you think biologists could use to study seed dispersal?

Other is many tools that researchers and use apart from the use of insects. They include use trapping devices to catch animals or birds.

Time to brainstorm ideas! a. How would you conduct a study to investigate seed dispersal by wind? I. State a research question you would investigate. ii. Describe the kinds of data you would need to answer the research question. iii. What experimental design would you use to study this quest?

This study would be conducted through an experimental approach in a certain forest. The research question would be how does wind affect seed dispersal? The data needed to answer this question is the amount of seeding that has been dispersed of a specific tree, the distance of these seedlings from the plant, the amount of germinated seedlings, the distance of those germinated seedlings.

The experimental design that I would use to investigate these questions would isolate various species of trees so that there is no confusion when gathering data. It would require finding tree species that are well spaced so that the seeds found would be that of the specific tree only.

How would you conduct a study to investigate seed dispersal by birds? I. State a research question you would investigate. ii. Describe the kinds of data you would need to answer the research question. iii. What experimental design would you use to study this question?

This study would require gathering data on the questions needed to answer and analyzing the data. The research question would be factors affecting seed disposal by birds. Some of the data to be collected would be the number of seeds dispersed by birds, amount of seeds that germinate and at what distance does it spread far away from tree. The experimental design would require to have a forest with multiple different species and collecting the faces from the area to know the dispersal rate.

What do the data in Figure 4 indicate about the survival of seedlings and saplings at different distances from the parental tree?

The survival rate is high since the seedlings are dispersed away from the parent tree, and they are not clustered together.

. Summarize the claim or claims the graph in Figure 5 is communicating

The graph from its representation clearly shows that not all seedlings that were dispersed in a certain area germinated and formed saplings. Again those seedlings dispersed far away from the mother tree had high chances of converting to saplings.

Considering Figures 4 and 5, summarize what the combination of seed, seedling, and sapling data tells you about seed dispersal by wind. Read More