Exploring Ecosystems With Children: Pollinators
This spring and summer take some time to introduce a young child to two profound lessons in science.
Two themes are easy but critical to explore:
1) Many different kinds of things live in and share an environment or given area,
2) Those things are interdependent, or they interact with each other.
These two ideas are central to Pre-K and elementary curriculums in science and outlined in the Next Generation Science Standards. So engage children’s attention early and frequently.
Do you need a starting point for initiating an investigation? How about exploring pollinators –those insects and animals that are central to the reproduction of most flowering plants? Learning about pollinators can help to tie these two concepts to everyday experiences in nature.
Pollinators, or insects, birds, bats, and even humans, help to transfer pollen from anthers (male part) to stigmas (female part) of either the same or different flowers. Ninety percent of the world’s flowering plants need the help of a pollinator. Flowers that are not pollinated cannot produce fruits or seeds, and therefore, cannot reproduce.
Almost 30% of all agricultural food crops come from flowering plants and/or trees that need pollinators to help them reproduce, thus about every 1 in three bites of non-meat or dairy food would not exist without the work active pollinators. Not only do we eat the fruits, vegetables nuts and berries that result from pollination of flowering plants, but some of our clothing and medicines are also from plants that, unless they were pollinated, we would have to do without.
Please note that some plants self-pollinate, and the wind carries pollen for other plants. Rice, corn, wheat and other grains and grasses like barley and oats are agricultural crops that don’t produce obvious flowers. These types of plants without showy flowers are self- or wind-pollinated.
Although pollinators do a significant amount of work, they don’t do it just because they can. Pollinators benefit from this arrangement too. Flowers often provide food awards. Pollen is a source of protein. Pollinators also may be compensated in the short term with a drink of the sweet nectar in those flowers. Bright colors and fragrances advertise the availability of nectar. In some cases, longer-term rewards for pollinators may be in the fruits or seeds that eventually result from successful pollination. Those plants also provide animals with shelter and nest sites. Thus pollinators and the plants they pollinate live in the same area and are interdependent. If you will recall, these are the two general themes you are trying to illustrate by discussing pollinators.
In this post, we are focusing on the topic of pollinators. If interested in broader coverage of insects, birds, or blossoms, please see the following descriptions of activities on this blog.
What plants do you see and which have flowers?
What do you know about flowers or how they grow and reproduce?
What insects do you see and which ones like those flowers?
What or who are pollinators?
What do they do and why is it important?
How are animals and plants interdependent?
What does it mean to “coevolve”?
How do you feel about bats or bees?
Before diving into the topic of pollinators, perhaps a good concept to establish is that although many different kinds of plants grow in one area, they all don’t need pollinators. You and your child can make a game of this. As you drive/walk to and from school, or to run errands, name as many kinds of plants as you can. Your child’s initial focus is likely to be on other general groups such as trees, bushes, flowers, lawn grass etc. Once your child establishes generalized groups, then you can try to refine that by beginning to notice (point out) variations. There are trees that produce blossoms and others that do not. There are plants with flowers and others without. As you are discussing pollinators, you really want to find plants with flowers.
A very basic distinction in the Plant Kingdom is that plants are either flowering or non-flowering. Flowering plants again fall into two major groups – ones that produce seeds enclosed in a fruit (angiosperms) as opposed to plants with “naked seeds” (gymnosperms). Pollinators have evolved an intimate interdependency with certain groups of angiosperms – specifically those with showy flowers. The mutual benefits of rewards for the pollinators in exchange for effective fertilization for the flowering plant is a win-win. This led certain groups of plants to make showier or more specialized flowers over time to more effectively attract specialized pollinators. This mutually beneficial feedback loop allowed for rapid species expansion into all ecological niches available for terrestrial plants. As a result, although relatively young in evolutionary terms, angiosperms are the most diverse group of land plants with over 350,000 different species.
The takeaway lesson of this observation is that the presence of showy flowers strongly suggests that there is some kind of pollinator involved. And if you are going to observe pollinators in action, then looking at flowering plants when they are blooming is the way to go.
Other variations you can suggest:
- Take a walk in a flower garden or park and observe the activity around flowering plants. Notice the types of plants and what kinds of insects or animals are active around them.
- Observe the same area under different weather conditions. What happens to these areas on a rainy day? Are the insects out and about? If you don’t want to get wet even sunshiny versus cloudy overcast days could make a difference.
- How about comparing these mini-ecosystems in the early morning, when the sun is fully out at noon, or at dusk? Are there differences in the activity of the insects or the plants they are partnering with?
When you think of mutually beneficial relationships between plants and insects or animals, the concept of an ecosystem is beginning to take form. Reflect that a number of living things are in an area and interact with each other, and then you can begin to assist your child in targeting observations to look for pollinators. Pollinators represent familiar organisms, insects, birds, and bats, thus they are an easy access point for understanding the notion of interdependency.
But FIRST, you will need to make sure your child has an idea what pollen is. Pollen is either a fine or coarse grained powder. In flowers, it is found on the anther. Looking down on most flowers, the pollen should be obvious. Flowers needing pollinators face outward exposing their reproductive parts.
Invite your child to take a look at pollen in flowers with a hand lens, noting its color or texture. Perhaps encourage her to examine pollen on flowers that are not currently being visited by a bee or other insect so as not to disturb their pollen collection.
If still interested, provide her with several Q-tips and ask her to carefully collect pollen samples from different flowers (and to keep the Q-tips separate from each other to avoid cross-contamination). Try to keep track of where the samples came from by labeling if possible. Again, the names of the flowers may not be known, but the samples can be organized by the color of the flower or location in a garden.
Examine the samples, noting differences. Every plant species has a distinctive pollen signature and this is often reflected in the shape and size of the pollen grains. Pollen can be sticky and non-sticky. It comes in different colors. It also is located in different places in different varieties of flowers. In some cases, it is sticking out prominently and in others, it is hidden deeper inside of the plant structure.
What kind of pollens did you find or can you see on the Q-tips? Are there variations? Pollen from one type of flower cannot fertilize another type of flower. The pollen has a distinctive signature as noted, and it is only familiar to that species. When the pollen matches, it will do its job.
When up close with those flowers, either looking or collecting pollen, note their fragrances. Find the language to describe these smells.
Once your child has some familiarity with pollen, it is finally time to begin a discussion of pollinators.
Sitting and waiting for an animal to pollinate may be a tad boring, so encourage running around, perhaps chasing a butterfly or moth. But to observe pollination, you can’t run around just anywhere. Choose a spot with a large flower garden or blossoming trees.
If a bee is the best and most obvious pollinator around, you may need to have a conversation about how to be courteous to and careful around bees.
After these initial free and unstructured observations, create a plan. Several options are available, but see what your child thinks. She can focus on an insect such as a bee or butterfly, or alternatively focus on a flower. As a start, find the language to describe the insect or flower of interest. For flowers, their color and scent are important. Color is a visual cue for an animal. Scent is a chemical cue. For the insect, its physical characteristics are important, but so too are its behaviors. What does it do when it comes near to a flower? Does it land on a petal or hover? What sound does it make?
If observing an insect, choose a time period to watch. The length of time may depend on your child’s interest, the insect’s speed or movement, or the distances it covers. Ten seconds may be a good starting point. What does the insect do within that time period? How many flowers does it visit, or how long does it remain on a flower? Do they visit if the flower is in the sun versus in the shade? (Remember that the temperature will vary if the flower is in the sun versus shade. Is temperature affecting the animal’s behavior?)
If observing a flower, watch it carefully, counting the number of insect visits, time spent, and evidence of pollen transport.
Compare and Contrast
What characteristics do pollinators have that help them to capture and transport pollen? Pollen is like a powder, so what might you need to pick it up? Think of a bee or bat’s furry coat. A flower’s nectar is deep inside, so what does an insect or bird need to access that sweet deliciousness? Butterflies and moths have structures near their mouths called a proboscis, or a straw-like structure they can sip through. Why? How about a hummingbird? What about a hummingbird is going to be helpful in extracting nectar (a long beak and tongue to go with it)? Tongues aren’t like straws so a hummingbird drinks nectar the same way your pet cat or dog drinks water. It “laps it up”. The nectar is beyond the pollen, so the animal’s efforts to get to the nectar results in pollen collection.
Compare flowers that attract pollinators versus those that don’t. Allow your child to sort through his observations, but here are some differences that you can nudge him to think about.
Do you have a favorite flower? You will see that pollinators have their favorites as well? Flowers have developed different characteristics to ensure that the best pollinators will return over and over.
- Bees prefer brightly colored flowers that are fragrant and sweetly scented (but they can’t see red). Bees collect pollen on their fuzzy coats and in baskets on the backs of their legs. They also eat the pollen and drink the nectar. They carry pollen and nectar back to the hive to share!
- Butterflies prefer large flowers or clustered flowers they can sit on and then use their long straw-like tongues, or proboscis and sip the nectar. Their color preferences are red, yellow, orange, pink and purple flowers.
- Flies prefer flowers with “nasty” aromas. (Some flowers even smell like dead animals.)
- Beetles also like large flowers, but white or duller colors. They prefer strong fruity, yeasty, or spicy fragrances. Beetles eat the pollen.
- Moths will collect pollen at night, so the flowers have to be white or light enough to see. These flowers also have to have a strong scent. The color and strong fragrance are important for finding the flower at night.
- Hummingbirds have keen eyesight, but their sense of smell is not well developed. They prefer red tubular shaped flowers, but also pink, orange and yellow will do. Fragrances are not so important because they cannot smell them anyways. Hummingbirds need a great deal of energy to keep their wings going, so the flowers they visit will need to produce large amounts of nectar and they have to visit many flowers in a day.
- Bats, like moths, will pollinate at dusk or at night. They too prefer flowers that are pale or white and very fragrant. They feed on insects, but also nectar, thus, those flowers produce significant amounts of this food source. Bats are important pollinators in tropical and desert areas.
Here is some more information on these animals and the flowers they are attracted to:
Compare animals that help transport pollen to animals that help to transport seeds, thus also assisting plants in propagation. Some animals will pick up seeds on their coats and later the seed falls off in a different location. Other animals eat the seeds that are not digested and end up in their excrement (or poop, whatever word your child understands and uses). That poop hits the ground and may have a chance to grow. Other animals such as squirrels help bury those seeds.
Humans help to disperse seeds too. We may carry them unintentionally on our clothing. A seed can get stuck to our pants or socks, and fall off later. We also intentionally collect, transport and plant seeds. In fact, of all the animals, people are best at dispersing seeds. (Remember also that seeds can be dispersed by the wind and water).
From the observations made earlier, you can invite a child to sort the animals observed, into categories such as insect, bird, or mammal. Other categories you can suggest include flying, crawling and walking, or the number of legs or wings observed.
A good topic to bring up regularly, and here is not an exception, is the idea of what organisms need to live.
There are 5 elements, or
- and the temperature matters as well.
We are exploring the concept of interdependence among living things, but they are also all dependent on these five factors for their survival. Compare and contrast the food needed by different organisms, or amount of sunlight or water.
Compare the structure of plants to animal structures that may have co-evolved. Flowers that have strong fragrances attract animals with a good sense of smell. Tubular flowers attract animals with long beaks or tongues for accessing their nectar. Bees have developed fuzzy bodies and bristles on their legs to transport pollen for honey production.
Counting the number of flowers an insect visits, or the number of different insects visiting a particular flower in a given amount of time.
If you have access to a variety of flowers, measure the distance to the bottom of the flower where the nectar is. Think about how long a butterfly’s proboscis or hummingbird’s tongue needs to be to claim this reward. Alternatively, how far an ant or small bee needs to crawl to get to the nectar
Take a pipe cleaner outside and find the nearest flower or blossom. “Fly” the pipe cleaner into the flower and “walk” it around (or hover). By this point, your child has observed an insect doing these things and she can use the pipe cleaner “insect” to perform the same behaviors. Is there evidence of having attracted pollen? “Fly” to another flower and repeat the same behaviors. Is there evidence that pollen was transferred?
Find several different flowering plants, maybe 1 or 2 for younger children and 3 or 4 for an older child. These should all be flowers that are blooming in an area nearby that can be observed. Invite your child to smell those flowers. Describe the scent, even if it is just in terms of strong or weak. If your child is so inclined, encourage finding other words for describing a scent. Think of the way we describe wines or perfumes. Does the smell remind him of citrus or fruit? Maybe it’s sweet or sour.
Now, suggest that your child make a prediction about which scent is most likely to attract a pollinator. Does he think a bee would prefer sweet or stinky? How about a fly?
Having made a prediction it is time for data collection. Observe these flowers over a predetermined period of time, noting how many times a pollinator visits. Compare the results of counting those visits. Is there a flower that was clearly preferred or visited more often? What was its smell or the attraction to those pollinators?
If making observations over several days, the flowers of interest are likely to change, or age. As they get older, what happens to them? Note changes in color, shape or scent. Are they visited more or less as they age?
Instead of smell, this experiment can be repeated with the color of the flower being the main characteristic of interest. Do bees prefer yellow, white, pink or red flowers (see above)?
Try the taste of nectar. Honeysuckle is an obvious choice. Hopefully, you have some that grows in your area, you know how to identify it and extract the delicious nectar inside. If not, here is a video describing this process.
Every child should know how to identify and extract nectar from honeysuckle!!! It’s a right of passage.
Visit a nursery or seed store and purchase and plant flowers or flowering plants that will attract the pollinator you are most interested in. If the plant grows, did it work? Did a pollinator find it?
Elaborate and Glossary
Visit a butterfly garden exhibit.
Not every plant is designed to attract a pollinator who will transport that pollen. Some plants are designed to attract those same insects because they are supper! Explore plants that can trap and kill pollinators. Here is a description of carnivorous plants:
In an ecosystem, each living thing has its own niche or role to play. But ecosystems can be disturbed or threatened. Recently very large numbers bees and bats have been dying off due to pesticides and disease. Why might this be important to us? Discuss the implications. Remember these animals are pollinating much of the food we eat. Bats are also important for consuming many insects, particularly mosquitos that can be a real pest.
Visit a commercial bee operation to learn how those bees help our farmers or how they make honey.
Go to a local nursery and learn about what kind of flowering plants are best for a butterfly garden. If you can plant a butterfly garden, that is even better!