Welcome to an exciting journey into the world of spiders! Today, we’re diving into some fascinating facts with Dr. Petra Sierwald, an expert in insects and spiders at the Field Museum. Even though spiders aren’t insects, they belong to the same larger group called arthropods, which also includes insects, millipedes, and centipedes. Let’s learn more about these amazing creatures!
Did you know there are over 45,000 known species of spiders? And that’s not all! Scientists believe there could be as many as 70,000 to 75,000 species out there, waiting to be discovered. That’s a lot more than the number of mammal species on Earth!
Many people find spiders a bit scary, and there are a few reasons for that. Spiders have long legs compared to their bodies, which can make them look creepy. They also move in ways that can be unpredictable. However, most spiders have fangs too small to bite humans, so the chances of being bitten are very low.
With so many spider species, how do scientists tell them apart? One way is by looking at their eyes. Spiders have eight eyes, and the pattern of these eyes can help identify different families of spiders. But eyesight isn’t the main sense for many spiders. They are excellent at sensing vibrations, which helps them detect prey and communicate with each other.
Spiders have unique ways of reproducing. Male spiders perform special movements to attract females. They have complex organs at the end of their pedipalps, which look like tiny boxing gloves. These organs are used during mating and are different for each species, helping scientists identify them.
Spiders play a crucial role in our ecosystems. They help control insect populations and are part of the food web. By studying spiders, scientists can learn about how species are distributed across the planet and how they respond to changes in the environment, like climate change.
Here’s a cool fact: although spiders can run fast, they tire out quickly. They have their heart in their back and need to pump blood into their legs to move. After about ten seconds of running, they run out of oxygen. So, if you ever need to, you can outrun a spider!
Spiders are incredible creatures with a lot to teach us about the natural world. Next time you see a spider, remember all the amazing things they do for our planet!
Research a specific spider species and create an informative poster. Include details about its habitat, diet, and unique characteristics. Use drawings or printed images to make your poster visually appealing. Share your poster with the class to teach others about your chosen spider.
Using images of different spiders, identify the eye patterns and match them to their respective families. Create a chart that shows the eye pattern and the spider family it belongs to. This will help you understand how scientists classify spiders based on their eye arrangements.
In pairs, research the mating rituals of a specific spider species. Create a short skit to demonstrate the unique movements and behaviors male spiders use to attract females. Perform your skit for the class and explain the significance of these rituals in spider reproduction.
Draw a food web that includes spiders and their role in the ecosystem. Identify the prey they help control and the predators that might eat them. Discuss how changes in the environment could affect this web and the importance of spiders in maintaining ecological balance.
Conduct an experiment to observe how quickly spiders can move. Create a small obstacle course and time how long it takes for a spider to navigate it. Record your observations and discuss why spiders tire quickly despite their speed, relating it to their unique physiology.
Here’s a sanitized version of the provided YouTube transcript:
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– We’re back here at the Field Museum with Dr. Petra Sierwald, who is an associate curator in insects. Today, what are we going to talk about?
– Spiders, of course, my favorite.
– But spiders aren’t insects.
– I know, I know. But they are also arthropods, and the methods we use for preservation for insects, at least for some of the insects, are the same that we use for spiders and other arachnids, as well as myriapods – millipedes and centipedes. We have over 45,000 described spider species. For some of the fauna, for example, in the soil, we expect that 40% may yet to be described.
– Wow.
– So we have a lot of unknowns there. So there could be as many as 70,000 to 75,000 species of spiders.
– Yes, easily, yes.
– So like, 20 times the amount of mammals? I’m not great at math. I actually don’t know what the ratio is.
– Yeah. It seems to me that things like spiders and scorpions elicit a really negative response from people. Why do you think that is?
– Spiders do have many legs, and the legs in relation to the body are a lot longer than in insects, which may contribute to that perception. They can look a little more creepy, and they move in unpredictable ways. But I think the main reason is that people don’t know enough about spiders. Yes, all spiders are predators, but the vast majority have fangs that are far too small to penetrate human skin. So the chance of being bitten by a spider is really remote. Not impossible, but really remote.
– Yeah. When you’re looking to learn more about spiders, what are some of the characteristics that you look at to differentiate species?
– How do I recognize 45,000 different spiders?
– Exactly! That seems like a lot. Many spider families can be recognized just by the eye pattern and how the eight eyes are distributed around the head.
– But you mentioned that eyesight isn’t a primary sense for a lot of these spiders, so…
– For many spiders, it’s vibration. They are really good at sensing vibrations. Male spiders, for example, will court or perform courtship movements in front of or on the outskirts of the female’s web. Their copulatory organs are secondary organs and are not directly connected to the gonads. All 45,000 spider species can be distinguished by differences in their copulatory organs. The female has a duct system on her abdomen and sperm storage containers, where she keeps the sperm of the male alive. For her, insemination does not mean fertilization; the eggs are fertilized when they are laid. The males have a very complicated organ that is visible in one of the images on the screen.
– Oh, there it is.
– That is at the end of their pedipalps, which are the shortened hand-like structures that males and females have in front of their legs.
– They look like boxing gloves.
– Exactly. In adult males, this complex organ develops only once they reach adulthood. So whenever you see a spider that looks like it’s wearing boxing gloves, it’s a male. The survival of us and our planet depends on having functioning forests, fields, and habitats. We want to know how many species we have, how they are distributed, and how changing climate, weather, and shifting temperatures affect them. These spider species will react to these changing conditions. We can use these relationship studies to investigate biogeography and understand how certain species are distributed.
– Because that gives context for how other animals, plants, and creatures have moved and migrated throughout the Earth’s changing climate over the last 600 million years.
– Yes, I conducted a study on African nursery web spiders that have close relatives that migrated from Africa all the way to Southeast Asia and reached Australia.
– If you could have any takeaway message for people who have reservations about spiders, what would you say to them?
– I think one of the most important things to consider is that although they have eight legs, they actually run out of oxygen very quickly. They have their heart in their back and need to pump blood into their legs to stretch them. So, they can run very fast for a short time—about ten seconds. After that, they quickly run out of oxygen. So, you can always outrun a spider.
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This version maintains the informative content while removing any informal or potentially inappropriate language.
Spiders – Spiders are arachnids, a group of joint-legged invertebrates that also includes scorpions, ticks, and mites. – Spiders play an important role in ecosystems by controlling insect populations.
Species – A species is a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. – The giant panda is an endangered species that relies on bamboo forests for survival.
Ecosystems – An ecosystem is a community of interacting organisms and their physical environment. – Healthy ecosystems provide services like clean water, air, and fertile soil.
Reproduction – Reproduction is the biological process by which new individual organisms are produced. – Insects like bees play a crucial role in the reproduction of many flowering plants through pollination.
Insects – Insects are small arthropods with a three-part body, usually two pairs of wings, and three pairs of legs. – Insects such as butterflies and beetles are vital for pollinating plants.
Arthropods – Arthropods are invertebrates with an exoskeleton, a segmented body, and jointed appendages. – Crabs, spiders, and insects are all examples of arthropods.
Climate – Climate refers to the long-term patterns of temperature, humidity, wind, etc., in an area. – Changes in climate can affect the habitats of many species, leading to shifts in biodiversity.
Vibrations – Vibrations are rapid motions back and forth or up and down. – Spiders can detect vibrations in their webs to sense when prey is caught.
Food – Food is any nutritious substance that organisms eat or absorb to maintain life and growth. – Plants produce their own food through the process of photosynthesis.
Populations – Populations are groups of individuals of the same species living in a particular area. – The population of monarch butterflies migrates thousands of miles each year.
