Natural History Notes

🦆 Week 1 Predators in the environment - adaptations in animals Eyes Adaptation → wide field of view ○​ Eg, American woodcock nests on the ground, therefore needing a large field of view. A woodcock can see around its whole body without having to turn its head. ○​ Fare apart eyes and far out eyes aloud to see around its body ○​ Eg, songbird, field of view around 300 degrees, ○​ Eg, mallard duck, field of view just under 360, eyes similar to American woodcock. ○​ Eg, White tailed deer, just under 360 ○​ Eg, Bullfrog, Large field, a view to adapt to the large amounts of prey and predators after them. The field of view is just under 360 degrees ●​ Costs of a large field of view (downsides) ○​ European starling, field of view 300 degrees ○​ Binocular vision (the part of vision where you can perceive depth ○​ Predators like the owl have a large field of view with a larger area of binocular vision, to time your attack when you're trying to catch prey ○​ The closer the eyes are together, reduces the field of view but the more binocular vision is increased. ○​ White-tailed deer, with eyes on the side of the head, increase the field of view. Deer have a rectangular pupil that helps increase the field of view (another adaptation). When the pupil contracts, it becomes skinnier, but the width does not change, resulting in the large field of view in bright lights. ○​ Whirligig beetles live at the surface between water and air. They can see when predators are coming from the sky and the water. They have adaptations in their head where they have two sets of eyes. A pair on the top and a pair on the button Ears ●​ Large external ears that stick out and act like satellite dishes that filter sound into the ears are found in lots of mammals due to their good sense of hearing. ●​ These external ears are called the pinna. ●​ Prey species tend to have large pinnae to capture sounds in a very large area ●​ Deer Mouse/White footed mouse always use their large pinnas to hear sounds in their environment. ●​ White tailed deer can shift their ears independently to hear around their body with limited movement. ●​ Little brown bat, Use their very large pinna to hear the echoes of their own sounds. ●​ These bats can hear the echoes of their prey to determine the distance of the object ●​ Moths have fine-tuned ears to listen for bats at night and avoid them. When they hear a bat, they fly in an erratic way to make it harder for the bats, or they stop flying and drop to the ground ●​ Moths and butterflies are a group of insects that we call Lepidopterans, meaning “scaled wings.” Their wings are covered in fine little scales ●​ These scales can absorb around 87% of the sound from a bat, meaning only 13% echoes back to the bat because the moth's body can absorb the sound (taking the echo out of echo location) Smell, how can they smell signs of predators ●​ Coyote poop, a volatile compound, is released by the poop, making a deer use the smell and the information from the poop to change its behaviours; it might avoid an area or increase its vigilance. ●​ Chemical Karimone, When an animal receives information, a chemical left behind by another animal, to its own benefit ●​ A water flea(Daphnia) hangs out where the food is at the surface of the water. When you add fish to the lake, the water fleas move to the bottom of the lake, where it's dark, so the fish can't see them. The fleas smell the chemical produced by the fish. When it is bright again, they go back to the top. They do something called vertical migration. The minute they smell the aromas of the fish, they change their behaviour. ●​ Physid snail, an easy meal for aquatic species, to avoid being eaten, they sense the hormones in their environment and change their behavior Camouflage → Background matching coloration Goal: avoid being noticed ●​ Grey tree frogs, bodies that look like trees to blend in with their environment. They can change their body in a matter of minutes, depending on their background. ●​ Carolina grasshopper, the same thing as the frog ●​ American Bittern lives in cat tail marshes due to its fine line details on its back ●​ Red-winged blackbird females have better camouflage because they have to protect the eggs to keep the species alive. Males want to be noticed by the females, so their camouflage is not that good. ●​ Vesper sparrow, Camouflage → Disruptive colouration ●​ The Northern leopard frog, legs have dark bands, making it hard to depict the frog's body ●​ Massasauga Rattlesnakes, dark patches over a pale background break the parts of the snake, making it harder to see. ●​ Eastern Milk snake, the body has large patches breaking it up ●​ The Canada goose has a disruptive coloration pattern on its chin. “Chin's strap”. When the goose is lying on its nest, the shin strap breaks the bird into two parts ●​ Killdeer, very loud, hard to see ●​ Red Eyed Vireo, lines on their head, on the top of the head is called a supercilium, and the one going across the eye is called the eyeline ●​ Raccoon, burglar mask on their face to conceal their eyes ●​ The wood frog also has a mask ●​ White tails deep have spots to camouflage in the ground when they lie down ●​ When alarmed, they can drop their heart rate by 68% so they don't have to breathe as much. This response is called Alarm bradycardia. Camouflage → Mascaraed ●​ Walking Stick imitates sticks or branches, which are not considered food by their predators ●​ Inchworms (caterpillars), many resemble twigs and branches; they can change colour depending on the stick they are on. They have light-sensing cells in their skin, allowing them to change colours without using their eyes. ●​ Giant Sawllowtal and pearly wood nymph, disguised as bird poop, making them undesirable to their predators. Decorative behaviour ●​ Beavers have large, strong teeth made from iron. They make a pile of mud and sticks for their lodge. It keeps them cool and warm. It allows them to hide from predators like wolves ●​ Tent Caterpillar, up to 300 caterpillars work together to create a large tent to live in and be protected against predators. Also acts like a greenhouse ot create a warm, cozy environment to help the caterpillars grow faster. ●​ Caddisfly larva, similar to moths and butterflies. Females lay eggs in the water. The larva gathers materials from its surroundings and constructs a home. ●​ Bagworm, caterpillars who build cases on leaves and hide in them ●​ Warty Leaf Beetle larva creates a case surrounding them, from material of its own feces. The mother covers each egg with feces and when they hatch the poop and grow their home. 🐢 Week 2 Autotomy, Startled Response, and Armours ●​ Hairstreak Butterfly- The end of the hind wings usually has red spots at the back and little filaments that have white tips (looks like antennae), which gives the illusion of a fake head with the goal of predators attacking there. ●​ Jumping spider: Good hunters that have big eyes, very good at hunting using visual stimuli, often get fooled by the antennae from the Hairstreak butterfly. Autotomy (Self-Amputation) ●​ Five-Lined skink- Skinks are a group of lizards (we only have one in Ontario). When they are juveniles, they have electric blue tails, which is an attractor for predators. (Predators attract the tail instead of the head). ○​ Hangout mostly on rocks. Caudal Autotomy is used by lizards (dropping their tail). Vertebrae of lizards have pre-determined breaking points for the tail (typically clean cut). Can drop their tail more than once, but must be higher up than the original cut off (new tail is only cartilage, not vertebrae so no breaking point) ○​ Lizards use their tail as a storage organ ○​ Lizards use their tails to balance themselves; those lizards who loose their tail typically have reduced speed and energy, which requires a lot of energy for reproduction ●​ Dark Fishing Spider - leave a leg behind during an attack to run away. Startle Response ●​ Underwing Moths have bright coloured underwings which they show to predators, which gives them a startled response, allowing the moth to fly away. ○​ Forewings are folded over the hind wings; hind wings are exposed when startled to scare off predators ●​ Carolina Grasshoppers have bright yellow colouration on their wings, which are only exposed when flying ●​ The Io Moth is a very bright coloured moth, it opens its front wings and exposes their hind wings, which are brightly coloured with two large black dots like eyes, called Eyespots. The eyespots make the animal look like something much bigger, making predators afraid. ●​ Polyphemus Moth has eye spots on the forewings and hind wings, but they are more prominent on the forewings ●​ The Canadian Tiger Swalltail also has eyepots that make it look like it is paying attention, located further away from its head. The head is tucked underneath its body ○​ If a predator comes too close to a pair of fleshy appendages with a stick out of the first drastic segment looking like a sneaker, these are called Osumeteria ●​ Green frogs make a high-pitched squeak when approached by a predator, giving them time to get away Armour ●​ Spotted Turtle uses their shell as a form of armour, which allows them to protect themselves from predators ○​ The shell of a turtle has two main parts made out of bones covered by a thin sheet of keratin: ■​ Carapace: top of the shell ■​ Plastron: belly of the turtle ○​ The ribs of turtles are very wide, fused with one another ○​ Their shoulder blades are inside of their rib caged which is very strange for a land animal ○​ When there is a predator, they tuck their limbs inside of their rib cage (hiding in their shell) ●​ Blandings turtle have a very helmet-like shell, and a bright yellow throat ○​ In the center of their shell, they have a hinge, which allows the shell to close or articulate, which makes it hard for predators to get inside of its shell and get its limbs and head. They can completely hide their limbs in their shell ●​ River Otters hunt for turtles in the winter, hibernating at the bottom of the lake ●​ Mollusks, shells made of calcium carbonate, have three layers: 1)​ Prismatic Layer→ made of big calcium carbonate crystals. (Looks like prisms under microscope) 2)​ Organic layer 3)​ Nacreous Layer → made out of a material that only mollusk species can create called Nacre, the material that pearls are made out of. It's an iridescent material that gives the shell a pearly look inside. It is made of a special type of calcium carbonate called aragonite (95% of the nacre layer is made of aragonite), made like a brick wall ○​ Bivalves: meaning two valves (muscles, clams) ■​ Eastern Ellipso ○​ Gastropods: Snails and slugs ■​ Brown-lipped snail Spines ●​ North American Porcupine (Canada’s second largest rodent), defends itself against predators using its quills (quills are modified hairs that are prickly), a porcupine can not shoot its quills ○​ Quills have several adaptations, such as barbs, which help the quills get in and stick inside a potential predator. The barbs will snag on flesh when trying to be pulled out. ○​ Quills have mechanisms that allow them to detach from the porcupine's body to stay with the predator ●​ Pumpkinseed sunfish has a bunch of spines located on the fins ○​ Dorsal fin, located at the top ○​ Anal fin is located at the back of the bottom ○​ Caudal fin is located at the tail ○​ The pelvic fin is located at the bottom ○​ Pectoral fins on the sides of the fish ●​ Yellow bullhead (catfish) & Northern Madtom (catfish) spines in their body as well as on the dorsal fin and the pectoral fin (very large and bony). These fish are venomous; the spines are connected to a venom gland. ●​ Io Moth Caterpillar venomous animal, but it only uses the venom for defence purposes. It has spines all over its body containing venom glands. The tip of the spine stays stuck in the predator, which causes irritation ●​ Spiny oak slug moth, lots of spines with venom, only used to hurt predators ●​ Milkweed Tussock Moth has very fine spines that look like hair, almost like tiny barbed wire with poison Chemical Defenses ●​ Massasauga Rattlesnake, Ontario's only venomous snake ●​ European paper wasp, bees and wasps belong to a group called Hymenoptera (clear wings) this group is considered toxic, through the sting used to kill and defend themselves ●​ Honey Bee, only have the sting for defence they have a venom sac in their butt, ○​ Stinger has three parts: ■​ Stylet ■​ Lancet (right) ■​ Lanet (left) ○​ Lancets are barbed; one will move up while the other goes down, the barbs aren’t aligned (acts as a drill), ○​ Apitoxin (api meaning bees) is the venom in honey bees ○​ When a honey bee stings it leaves the sac behind causing more venom to release ○​ It releases a compound that attracts other bees to attack the aggressor ●​ Blister Beetle, poisonous not venomous, only the male can produce the toxin which is stowed in their blood, when they are harassed they ooze out the toxin (cantharidin) but the male will give it to the female for protection. ●​ American Toad produces toxins (bufotoxin) through glands on their back, not toxic to the touch however is distasteful and can produce side effects if ingested ○​ You are more likely to hurt a toad if you handle it than it hurting you, cause they have thin skin and toxins form your hands will get absorbed into their blood stream ●​ Eastern Newt (Red EFT stage) are packed with toxin called tetrodotoxin which is 25x more toxic than potassium cyanide ○​ Juveniles live on land adult one lives in water the adult is 10x less toxic then the Redd eft ○​ The colours of the red eft show its toxic to predators ○​ When you have the combination of bright colours and toxicity its called Aposematism ●​ Monarch caterpillar, it is an example of a high contrast aposematic colouration, with the contrast of bright and dark colours ●​ Cardiac glycosides are a toxin on the leaves the monarch butterflies feeds on, the caterpillars store the toxins in their body and are immune to them. ●​ Aposematic colouration: (geneticaly determined) ○​ Monarch caterpillar ○​ Oleander aphid ○​ Milkweed Tussock Moth (caterpillar) ○​ Red Milkweed Beetle ○​ American giant millipede which contains Benzoquinone which is a chemical in which is very distasteful and can also cause a chemical burn on the skin ○​ Black and gold flat Millipede produces a toxic compound and releases hydrogen cyanide gas from its glands ○​ Stripped Skunk ew stinky pee yew, sprays stinky, mainly nocturnal, ○​ Porcupine ○​ Grey tree frog, pickerel frog, bright colouration on legs (only exposed when stretched) ○​ Dogbane Tiger Moth advertises its toxicity shows the aposecematic computation in the night with bats ○​ Prairie Rattlesnake a form acoustic aposematic, will rattle tail when feelings threatened, tail has a bunch of segments within one another and when it shakes they bump together and create the sound, can twitch 90x per second ●​ When different toxic animals have the same colour patterns, predators begin to associate those colours with danger. ●​ Fritz Muller ○​ Mullerian mimicry many toxic species sharing a similar aposematic colouration ●​ Henry walter bates ○​ Batesian mimicry, non toxic a species will carry similar colours to imitate the aposematic colouration ○​ Hover fly, Locust borer, Bee mimic flower beetle are examples this mimicry 🌵 Week 3 Defences Physical Defences White-tailed deer, an herbivore, can eat about 1 metric tonne of plant tissue a year and a moose can eat 10x that Insects are the most numerous and important herbivores ●​ Eastern tent caterpillar ●​ Aphid Plants have developed defences against herbivores, such as prickles or thorns that stab herbivores in the mouth. ​ Brittle Prickly Pear grows in rocky, dry habitats and has spines to prevent animals from eating their tissue. Spines are modified leaves that no longer photosynthesize Hawthorn, a plant, has modified branches into very long and pointy thorns Roses don’t have thorns; they have pickles Prickly ash, the leaves look like ash Great Mullein has fine branching hairs covering the surface of the leaves (trichomes), insects have a hard time walking on the plant and can't feed on them Great Stinging Nettle leaves are toxic (glomerular trichome), and stinging needles work similarly to a pipette. Always produces some amount of tricomes, produces more when under attack (induced defence). If a plant experiences little herbivory, it will have few trichomes. If a plant experiences a lot, it will form many trichomes as it grows new leaves. ●​ Defences that are always part of a plant are called constitutive, Souringrush horsetail (identified as a type of fern), about 20% of the plant is made out of silica. These silica accumulators accumulate silica into structures in their tissue called phytoliths (phyto = plant, lith = rocks) Plants need silica for many things. In grasses and horsetails, silica protects them from large herbivores and will wear out the teeth of the herbivores. Skunk Cabbage manufactures crystals of calcium oxalate (Material), and the crystals are called raphides, small shards that are stored in special compartments called isoblasts (where the raphides are). Chemical defences Plants also use molecules to defend themself Structural - not made primarily by the plant to defend itself, but molecules that are necessary for the plant to hold itself together The 2 most important structural molecules in a plant are cellulose and lignin, located in the cell wall of the plant. Wood and bark are heavy in lignin, making it hard to digest Secondary metabolites, secondary because they don't play a role in the plant, their only function is to deter animals from eating the plant. Ex: cocaine, caffeine, morphine, nicotine Porcupine and Red Oaks, Oak leaves are hard to digest because they are full of molecules called tannins (secondary metabolites). Tannins will interfere with the digestion of proteins Prickly ash has pickles on its branches and stems. If you crush the leaves, you will get a pleasant lemon smell, which deters predators. The molecule that is produced by the prickly ash is called limonene, which is part of a larger group of chemicals called terpenoids. Exclusively to deter herbivores Eastern Red Cedars also produce terpenoids (Cedrol) Common Milkweed, ooze sticky toxic substance called latex when leaves are broken. Some animals will eat is and it will seal their mouths, and they will die Latex evolved independently 10% use latex as a defence Eastern White Pine creates a liquid called oleoresin stored in canals in the wood of the tree Balsen fir, resin stored in blisters in the bark, white, oozy stuff Posin ivy, Urushiol, the resin in the plant Cicadas, ecdysis, the process in which insects moult their exoskeleton made from a hormone call ecydysone, Bracken Ferm, phytoecdysone is a mimic of ecdysone Chemical defence and partnerships Digestion involves the breakdown of proteins into amino acids, using enzymes called proteases Protein inhibitors interfere with the process of protein breakdown into amino acids Methyl Jasomate has been recently shown to turn caterpillars into cannibals Domatia are mite shelters to keep mites around Mutualistic Symbiosis: Symbiosis = a close association between two or more species. Mutualistic = mutual benefits (win, win situation)\ 🐦 Week 4 Surviving Winter ●​ Freezing temperatures are a big challenge for all living organisms because living cells can not survive freezing. ●​ Think of cells as a little bag of water with a membrane inside. If the fluid freezes, the cell dies; there are a lot of problems, including dehydration and puncturing of organelles through ice crystals. ●​ All living organisms must find ways to protect the inside of their cells from freezing. First strategy: Migration ●​ Go somewhere that does not have freezing temperatures, only available for birds that fly and insects that fly. ●​ Things that trigger migration behaviour: ○​ Reduction in food supply ○​ Change in light intensity ○​ Most important: Change in day length (Photoperiod) ■​ Zugunruhe → migratory restlessness ■​ Hyperphagia → Excessive feeding (double or triple body weight for migration) Red Eye Vireo, leaves for the winter, is a long-distance migrant, and spends winter in places like Brazil Red-winged Blackbird, don't migrate as far American Robin, a species that has migratory populations and resident migrants, where they stay year-round Ring-necked Duck Hyperphagia: During the period of Hyperphagia, when the bird is eating a lot, the size of their digestive tract and liver increases to take in the food; however, as soon as migration starts, the organs shrink to minimize the energy needed for their organs so they can use that energy for flight. Yellow rumped warbler needs to double or triple its body weight for migration. They develop so much fat Plants and animals coevolved over many years, so the berries on trees tend to grow at the time needed for migration. Semipalmated sandpiper stops in the Bay of fundy to feed, migrate form the Arctic to the coast of South America, 30% of the entire world population of these birds stop in the Bay of Fundy. Multigenerational Migrants: ●​ Green Darner is a long-distance migrant insect that migrates as far as the Caribbean or Florida. Multigenerational migration ●​ Monarch Butterfly, famous for migration, two Canadians, Frederick and Norah Urquart, figured out their migration patterns by tagging thousands of butterflies. Migrate to Mexico from Ontario, 4000km. Back north, the trip is different; they won't go all the way back to Ontario right away; they stop and produce new generations to migrate north to Ontario. Second strategy: Remaining Active ●​ Birds and mammals that can generate a lot of body heat and can remain active in winter. ●​ The reasons why these animals can stay active in the winter are that they are Endotherms. They can generate a lot of body heat. ●​ Most animals are Ectotherms, things like fish, amphibians, and insects. All animals except birds nd mammals are considered ectotherms. ●​ Not all mammals remain active; some go dormant For any animal to function properly in must balance a simple equation: Heat in (body heat)= Heat out (ways the body heat leaves) ●​ Ways that heat can escape… ○​ Conduction: direct contact, the legs holding on to a branch loose heat through the leg onto the branch ○​ Convection: transfer of heat through the movement of fluid or gas over an object. As cold air moves over the body, it takes away some heat. Black-capped Chickadee, this bird has to constantly produce heat to keep its body temperature at 38 degrees in an environment that is -15 degrees. -​ Retains heat almost as well as styrofoam How birds use their feathers to insulate themselves: ●​ The down feathers, ●​ The contour feathers: these feathers give the outline of the bird ●​ To keep warm, birds have to grow denser ●​ Birds can also puff their feathers by contracting muscles, trapping more heat between the body and feather. American Goldfinch increase feather weight by 50% in winter to reduce heat loss River Otter has great insulation from its fur, called the pellage. ●​ The fur coat of mammals is called the pellage ●​ 2 types hairs in the pellage: ○​ Guard hairs, long ○​ Under fur, thinner, shorter curly, serves mostly for insulation, really dense and thin North American Beaver, Very good underfur, Third strategy: Dormancy ●​ What we call hibernation ●​ Reduce their metabolism and activity, requiring less food in the winter. (in week 5) 2 factors that influence the rate of heat loss in animals 1.​ Size Heat production is proportional to the volume of an animal; however, heat loss is proportional to the surface area of an animal. We can then divide the surface area by the volume. Bergmann's rule = when a species exists over a large area, we tend to find larger animals in colder regions, probably because of the effect of size and surface area to volume ratio. Emperor penguins use a method called huddling, where they all stand close to each other to avoid heatloss. They huddle because… ●​ It increases the volume of penguins and decreases the surface area, increasing heat retention. ●​ Muscrats, raccoons, mice, and bats are all examples of huddling Golden-crowned Kinglet doesn't migrate and can only eat bugs and hibernating caterpillars. To saty warm at night, they huddle under trees and branches. 2.​ Shape Animals with more elongated bodies lose heat faster, requiring to eat more. Spherical animals conserve heat better. Roosts and lodges ●​ Many animals use roosts in the winter to stay warm. Such as hollowed-out trees. Screech Owl roosts in cavities in trees during the day ●​ Roosts help protect against heatloss by protecting them from the wind and by trapping the generated heat. Woodpeckers build their own roosts to nest and stay warm in winter. Animals like squirrels dig in the snow, making tunnels to protect themselves Ruffed gross roost in the snow Beavers are famous for building their own lodge/dam to protect against predators and stay warm in the winter. ●​ There is around a 25-degree difference between the outside temp and inside the beaver den. Musk rats also build lodges using vegetation. Large mammals can't build large lodges, so they use their environment ●​ In the winter, find patches on conifers offering shelter for deer. Sometimes in large groups called a yard. Lots of small animals are active under the snow and on top of the ground in what's called the subnivean zone, where the ground melts a bit of the snow, creating mazes. This zone is essential for small mammals, because their fur is not as thick. 🐿️ Week 5 Surviving the Winter part 2 ​ Staying Active Black-capped Chickadee - will enter its night roost with about 8% of its body weight in fat. When it comes out of the roost in the morning, it only has about 3% of its body weight in fat. ●​ Has to spend the day replenishing that reserve (get back to 8% body weight in fat) so it can stay warm the next night. In the fall, they hide food for the winter (food is harder to find in winter). Food Caching or Hoarding is when animals stash food for the winter. ●​ Have phenomenal spatial memory, which helps them remember food caches (where they hide food). Their hippocampus is larger than that of birds that don’t cache food. ●​ Scatter hoarding is when they scatter their caches all over the place, and not just in specific spots White-breasted Nuthatch, Blue Jays also cache food Red Squirrels - good examples of a larder hoarder, which is when they hide a lot of food, but in a few locations ●​ 26% of a squirrel's stache is going to get stolen by another squirrel ●​ 97% of red squirrels steal from other squirrels' caches Grey Squirrels - use a mix of larder hoarding and scatter hoarding Short-tailed Shrew - Largest shrew in North America ●​ Shrews are more closely related to carnivores like cats & dogs than they are to rodents ●​ Tiny eyes, pointy nose, barely visible ears, fur ●​ Feed on: Insects, Earthworms, Mollusks, Frogs, Salamanders, Mice, Voles ●​ Shrews, as a group, have the highest metabolic rate of all mammals, so they need to eat constantly ●​ Is a Larder hoarder, usually filled with dead or paralyzed animals ●​ One of the only known species of venomous mammal, they produce venomous saliva Blarinatoxin Northern Shrike - curved beak, songbird that thinks it's a bird of prey ●​ Missing talons (which birds of prey use to kill their prey). They impale their prey on thorns, then use their beak to tear apart. Usually use one particular location to impale their prey. Beaver - also build larders for the winter ●​ Put plants they don’t like as much on top to push desired plants under water, making it easier to access in the winter White-tailed deer - cannot cache food for the winter; they only eat plant matter, mostly foliage. Only available food in winter is conifers, which don’t have much nutritional value compared to plants available during spring and summer. ●​ Become desperate for food in the winter ●​ Browse line - Created by deer in the winter when the deer go on the ice and eat everything they can reach on the land (Usually trees such as cedars) ●​ Have to spend more energy in winter moving around since they have long, little, spindly legs, which aren’t suited to walking through the snow. The higher the snow, the more energy it needs to use (25% of the leg in snow = 25-50% in energy expenditure, 50% in depth = 100-200% increase in energy expenditure, 80% snow depth = 250-600% increase in energy expenditure) ●​ In winter, might spend more energy looking for food than the energy the food would give ●​ Usually walk in a single file and try to use the same trails to pack the snow down Smaller animals can move on the surface of the snow if they have large feet (act like snowshoes) Such as a snowshoe hare, fishers, martins, lynx, bobcats Dormancy Dormancy 🌱 Week 6 Light and Water Getting enough light (How plants obtain their energy) Autotrophs- organisms that can make their own food ​ Eg, plants, algae Heterotrophs - organisms that feed on other animals ​ Ex. Fungi, Photosynthesis ●​ Combinations of carbon dioxide and water Positive phototropism - tendency to grow toward the light Negative phototropism - tendency to grow away from the light Chlorophyll A- converts light energy into chemical energy Chlorophyll B- captures light and sends it to chlorophyll A (more sensitive to light) Red light = high-quality light Larger leaves on saplings are an adaptation to get more light Partridgeberry spreads along the ground to find more light for photosynthesis. Wild sarsparilla, sprouts in a bunch of places connected underground Adaptation, crawl on plants to go up and reach other plants and use tendrils to grow and move around and latch on to something. Ex. Vines, poison ivy Advantageous roots grow along trees and latch Spring ephemerals - Yellow trout lily uses the light in the spring to grow, then remains dormant, found in forests Water Goldonrod, grow in fields and meadows, they get two much light. When a plant heats up too much, they experience a lot of water loss. Adaptations to reduce water loss: ●​ Water loss in leaves → leaves can be covered in a waxy layer called the cuticle. Which is “waterproofing the leaf.” To be able to photosynthesis the plant leaf has an opening called the Somata. ●​ Smaller leaves, e.g., narrowleaf cattail, hold leaves at a steeper angle to capture less direct sunlight. ●​ Lilly pads, hollow tubes used to deliver oxygen to the roots. Peat Bogs and Carnivorous Plants Peat lands: wetland built by peat moss (sphagnum moss) several species. 📄 Study review Compendium of Natural Adaptations: A Comprehensive Study Resource 1. Sensory Adaptations: The Mechanics of Perception Sensory adaptations function as the primary interface between an organism and its environment, serving as the first line of defense for the vulnerable and an essential toolkit for the predator. Evolution has sculpted these systems—vision, hearing, and olfaction—through a series of strategic trade-offs. An organism rarely possesses "perfect" sensing; rather, it possesses specialized tools optimized for its specific niche. A predator may sacrifice a wide field of view for the depth perception required to time a lethal strike, while a prey species may abandon depth perception entirely to achieve a panoramic awareness that ensures no threat approaches unnoticed. Primary Sensory Categorizations Adaptation Type: Vision ●​ Wide Field of View: The strategic placement of eyes on the sides of the skull to maximize the visible horizon. ○​ American woodcock (can see 360 degrees around its body without turning its head), songbird (300 degrees), mallard duck (just under 360), white-tailed deer (just under 360), bullfrog. ●​ Binocular Vision: Overlapping visual fields that facilitate depth perception, critical for hunting and timing attacks. ○​ Owl, European starling. ●​ Rectangular Pupils: A specialized pupillary shape that increases the horizontal field of view. When the pupil contracts in bright light, it remains wide, maintaining panoramic awareness. ○​ White-tailed deer. ●​ Split Vision: A remarkable anatomical adaptation allowing simultaneous monitoring of two different mediums. ○​ Whirligig beetles (possess two sets of eyes: one pair for aerial surveillance and one pair for underwater monitoring). Adaptation Type: Hearing ●​ Pinnae: External ear structures that function like satellite dishes, capturing and funneling sound waves into the ear canal. ○​ Deer Mouse, White-footed mouse, White-tailed deer (can shift ears independently), Little brown bat (uses large pinnae to catch returning echoes). ●​ Sound Absorption and Scaling: The use of physical structures to negate predator sensing. ○​ Lepidopterans (Moths and Butterflies): Possess fine wing scales that can absorb approximately 87% of a bat’s echolocation, leaving only a 13% echo for the predator—effectively "silencing" the moth's acoustic signature. Adaptation Type: Olfactory and Chemical Sensing ●​ Volatile Compounds: Airborne chemicals that convey complex information regarding predator presence. ○​ Coyote poop (detected by deer to inform behavior and increase vigilance). ●​ Kairomones: Chemical signals produced by one species that are intercepted by another species to the receiver's benefit. ○​ Water flea (Daphnia): Upon detecting fish chemicals, they perform Vertical Migration, moving to the dark depths during the day to avoid visual detection by predators. ●​ Hormonal Sensing: The detection of water-borne hormones to trigger defensive shifts. ○​ Physid snail. The Cost-Benefit of Eye Placement The architecture of the skull dictates an animal's survival strategy. For ground-nesting prey like the American Woodcock, eye placement is at the extreme lateral and posterior, granting a full 360-degree view. This allows the bird to monitor the entire landscape for threats without the betrayal of physical movement. However, the "cost" of this panoramic view is the loss of binocular overlap. Without binocular vision, depth perception is severely limited. Conversely, predators like the owl prioritize the "benefit" of binocular vision to calculate the precise distance of prey, accepting the "cost" of a massive blind spot behind the head. While sensory adaptations allow an animal to perceive a threat, the next stage of survival involves ensuring the threat does not perceive them. -------------------------------------------------------------------------------- 2. The Art of Invisibility: Camouflage and Masquerade The strategic mandate of "not being noticed" is a primary survival mechanism. Camouflage is the manipulation of a predator’s visual processing, ranging from simple background matching to the active deception of the predator's brain. By breaking up a recognizable silhouette, the prey ceases to register as an organism and instead becomes part of the inanimate landscape. Reference Guide to Visual Deception Background Matching Coloration ●​ Definition: Patterns and colors that mimic the immediate environment. ●​ Associated Animals: Grey tree frogs (can change color in minutes), Carolina grasshopper, American Bittern (uses vertical lines to blend into cattail marshes), Female Red-winged blackbird (camouflaged for nest protection), Vesper sparrow. Disruptive Coloration ●​ Definition: High-contrast patterns that break up the body's outline or conceal sensitive features like eyes. ●​ Associated Animals: Northern leopard frog (dark leg bands), Massasauga Rattlesnake (dark patches over a pale background), Eastern Milk snake (large patches), Canada goose (white "chin strap" breaks the bird into two pieces while nesting), Killdeer, Red-eyed Vireo (supercilium and eyeline), Raccoon (mask), Wood frog (mask), White-tailed deer (fawn spots). Masquerade ●​ Definition: An active form of camouflage where the organism resembles an inedible object. ●​ Associated Animals: Walking Stick (twigs/branches), Inchworms (mimic twigs; possess light-sensing cells in the skin to match colors without using eyes), Giant Swallowtail and Pearly wood nymph (mimic bird feces). Decorative Behavior and Protective Cases Beyond natural coloration, some organisms utilize environmental materials to construct an external "cloak" of invisibility or defense. ●​ Warty Leaf Beetle: The larva creates a case from its own feces; the mother initiates this by covering the eggs in fecal matter. ●​ Caddisfly Larva: Constructs a protective home from surrounding aquatic materials. ●​ Tent Caterpillar: Hundreds of larvae cooperate to build a silk "tent" that acts as both a protective barrier and a thermal greenhouse. ●​ Beaver: Constructs a lodge of mud and sticks, a massive physical deterrent against predators like wolves. Physiological Supplements: Alarm Bradycardia Camouflage is often paired with physiological adaptations. When a White-tailed deer is alarmed and hiding, it may employ Alarm Bradycardia. By dropping its heart rate by 68%, the deer reduces its need to breathe heavily, allowing it to remain perfectly still and silent while the predator passes. When visual deception is compromised, the survival mandate shifts from passive evasion to mechanical and chemical confrontation. -------------------------------------------------------------------------------- 3. Active Defense: Autotomy, Startle Responses, and Armor Active defenses are the "last resort" mechanisms triggered by direct confrontation. These strategies aim to shock a predator, redirect a strike to a non-vital area, or present a physical barrier that renders the prey inaccessible. Defensive Strategy Data Cards -------------------------------------------------------------------------------Autotomy (Self-Amputation) ●​ Mechanics: The voluntary shedding of a limb or tail to escape a predator's grasp. The vertebrae often have predetermined breaking points for a clean cut. ●​ Associated Animals: ○​ Five-Lined Skink: Employs Caudal Autotomy. Juveniles have electric blue tails to attract attacks away from the head. The tail is a storage organ, so the loss is energetically expensive. ○​ Dark Fishing Spider: Will detach and leave a leg behind to facilitate escape. -------------------------------------------------------------------------------Startle Response and Eyespots ●​ Mechanics: Sudden displays intended to shock the predator’s nervous system, creating a window for flight. ●​ Associated Animals: ○​ Underwing Moths & Carolina Grasshoppers: Reveal bright, hidden colors on the hindwings only when taking flight. ○​ Io Moth & Polyphemus Moth: Feature large "Eyespots" that mimic the gaze of a much larger, more dangerous animal. ○​ Canadian Tiger Swallowtail: Uses eyespots located away from the head and may extend Osmeteria (fleshy, snake-like appendages) if a predator approaches the first thoracic segment. ○​ Green Frogs: Emit a high-pitched squeak to startle an aggressor. -------------------------------------------------------------------------------- Physical Armor ●​ Mechanics: Calcified or keratinized structures that enclose the organism’s vital organs. ●​ Associated Animals: ○​ Spotted Turtle: Utilizes a Carapace (top) and Plastron (belly) made of bone covered in keratin. ○​ Blandings Turtle: Features a hinged plastron, allowing the shell to seal shut entirely. ○​ Mollusks: Utilize calcium carbonate shells. Examples include Bivalves (Eastern Ellipso) and Gastropods (Brown-lipped snail). -------------------------------------------------------------------------------- Structural Analysis: The "Brick Wall" of Nacre The mollusk shell is composed of three distinct layers: the Prismatic layer (calcium carbonate crystals), the Organic layer, and the Nacreous layer. The biological "So What?" of this system lies in the Nacre. Composed of 95% Aragonite, nacre is organized in a microscopic "brick wall" structure. This specific arrangement makes it a superior structural material—exceptionally durable and resilient against the crushing forces of a predator's mandibles or teeth. While physical barriers are effective, many organisms utilize biological weaponry in the form of spines and complex chemical toxins. -------------------------------------------------------------------------------- 4. Chemical Warfare and Mimicry Systems Evolution has favored the development of toxicity as a potent deterrent; however, toxicity is most effective when it is "advertised." By signaling danger through bright colors or sound, toxic organisms avoid the energetic cost and physical damage of a mutual struggle. Toxicology and Mimicry Comprehensive List ●​ Spines and Venom ○​ North American Porcupine: Modified hairs (quills) with barbs that snag in flesh and detach from the porcupine. ○​ Yellow Bullhead & Northern Madtom: Feature bony spines on the dorsal and pectoral fins connected to venom glands. ○​ Io Moth and Spiny Oak Slug Moth Caterpillars: Spines contain venom glands that cause severe irritation. ○​ Milkweed Tussock Moth: Fine, barbed-wire-like spines containing poison. ●​ Chemical Defenses (Toxins) ○​ Honey Bee: Employs Apitoxin via a barbed stinger. ○​ Blister Beetle: Blood contains Cantharidin, a toxin produced by males and gifted to females for protection. ○​ American Toad: Glands produce Bufotoxin, which is distasteful and dangerous if ingested. ○​ Eastern Newt (Red Eft): The juvenile land stage contains Tetrodotoxin (25x more toxic than cyanide). Notably, the adult aquatic stage is 10x less toxic than the Red Eft. ○​ Monarch Caterpillar: Sequesters Cardiac glycosides from milkweed plants. ○​ American Giant Millipede: Releases Benzoquinone, which can cause chemical burns. ○​ Black and Gold Flat Millipede: Releases Hydrogen cyanide gas. ●​ Visual Warning Systems (Aposematism) ○​ Definition: Bright, high-contrast coloration signaling toxicity. ○​ Entities: Monarch, Oleander aphid, Red Milkweed Beetle, Red Eft. ○​ Acoustic Aposematism: The Dogbane Tiger Moth uses ultrasonic clicks to advertise its toxicity to bats at night. ●​ Mimicry Complexes ○​ Mullerian Mimicry (Fritz Muller): Multiple toxic species adopt the same warning patterns (e.g., various bees and wasps) to simplify the predator's learning process. ○​ Batesian Mimicry (Henry Walter Bates): A harmless species imitates a toxic one. Examples: Hover fly, Locust borer, Bee mimic flower beetle. The Social Strategy of Chemical Defense The Honey Bee demonstrates that chemical defense can be a collective effort. When a bee stings, its barbed stinger and venom sac remain in the target, continuing to pump apitoxin. Simultaneously, it releases an alarm pheromone that recruits the entire colony to attack the same aggressor, multiplying the defensive impact. While animals can flee or fight, stationary organisms like plants must rely on a different set of complex, stationary defenses. -------------------------------------------------------------------------------- 5. Botanical Defenses: Structural and Chemical Resistance Plants face the unique challenge of being stationary targets. They must employ both constitutive defenses (always present) and induced defenses (triggered by herbivore damage) to deter everything from deer to insects. Plant Defense Mechanisms Defense Term Associated Plants Spines (Modified leaves) Brittle Prickly Pear Thorns (Modified branches) Hawthorn Prickles (Epidermal outgrowths) Roses, Prickly ash Trichomes (Stinging hairs) Stinging Nettle (uses a "pipette" mechanism), Great Mullein Silica/Phytoliths Souringrush horsetail (20% silica), Grasses Raphides (Calcium Oxalate) Skunk Cabbage (crystal shards in isoblasts) Secondary Metabolites Red Oaks (Tannins), Prickly ash (Limonene/Terpenoids) Latex (Sticky toxins) Common Milkweed Resins/Urushiol Eastern White Pine, Balsam fir, Poison Ivy (Urushiol) Induced Defenses and Developmental Mimicry Plants are far from passive. The Stinging Nettle exhibits an induced defense, increasing the density of its stinging trichomes significantly after an initial herbivore attack. Even more sophisticated is the Bracken Fern, which utilizes Developmental Mimicry. It produces Phytoecdysone, a chemical mimic of the insect molting hormone, Ecdysone. When an insect ingests this, it triggers premature Ecdysis (molting), disrupting its life cycle and preventing it from reaching reproductive maturity. These defenses ensure survival during the growing season, but the ultimate environmental threat for many organisms is the onset of winter. -------------------------------------------------------------------------------- 6. Environmental Adaptation: The Winter Survival Mandate Winter survival is a physical equation of "Heat In vs. Heat Out." For cells, the primary threat is freezing; ice crystals can puncture organelles and lead to lethal dehydration. Primary Winter Strategies 1. Migration ●​ Triggers: The primary trigger is Photoperiod (change in day length). This induces Zugunruhe (migratory restlessness) and Hyperphagia (excessive feeding to double or triple body weight). ●​ Physiological Efficiency: In a remarkable feat of conservation, birds like the Yellow-rumped warbler will actually shrink their digestive tract and liver once migration begins to minimize the energy required to carry and maintain those organs during flight. ●​ Examples: Red Eye Vireo, American Robin, Monarch Butterfly (multigenerational migrant), Green Darner. 2. Remaining Active (Endothermy and Insulation) ●​ Bergmann's Rule: Larger animals have a lower surface-area-to-volume ratio, allowing them to retain heat more efficiently in cold climates. ●​ Insulation: Mammals utilize Pellage (Guard hairs and Underfur), while birds use Down feathers for heat and Contour feathers for shape. ●​ Social Huddling: Used by Emperor penguins and small mammals (Mice, Raccoons, Bats) to collectively reduce exposed surface area. 3. Shelter and Subnivean Strategies ●​ Subnivean Zone: The space between the snow and the ground, insulated by snow and warmed by the earth, where small mammals remain active. ●​ Shelters: Cavities (Screech Owl), Snow Roosts (Ruffed Grouse), and Lodges (Beaver). The Energetic Cost of Snow For the White-tailed deer, snow depth is a critical factor in the survival equation. Their spindly legs are poorly suited for snow, leading to dramatic increases in energy expenditure: ●​ Snow at 25% leg depth: 25-50% increase in energy used. ●​ Snow at 50% leg depth: 100-200% increase. ●​ Snow at 80% leg depth: 250-600% increase. To survive, deer "yard" together, walking single file to create packed-down trails that reduce the cost of movement. Ultimately, the ability to survive winter is tied to the efficiency of gathering, storing, and defending energy. -------------------------------------------------------------------------------- 7. Master Terminology Matching List ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ ●​ PINNA : Deer Mouse, White-footed mouse, White-tailed deer, Little brown bat. ECHOLOCATION : Little brown bat (countered by Lepidoptera scales). LEPIDOPTERA : Moths and Butterflies (possess scaled wings for sound absorption). KAIROMONE : Water flea (Daphnia) sensing fish. VERTICAL MIGRATION : Water flea (Daphnia). BACKGROUND MATCHING : Grey tree frog, American Bittern, Vesper sparrow. DISRUPTIVE COLORATION : Northern leopard frog, Massasauga Rattlesnake, Canada goose, Killdeer, Red-eyed Vireo, Raccoon, Wood frog. MASQUERADE : Walking Stick, Inchworms, Giant Swallowtail, Pearly wood nymph. DECORATIVE BEHAVIOR : Beaver (lodge), Warty Leaf Beetle (fecal case), Caddisfly larva, Tent Caterpillar. AUTOTOMY : Five-Lined skink (Caudal), Dark Fishing Spider. STARTLE RESPONSE : Underwing Moths, Carolina Grasshoppers, Green frogs. EYESPOTS : Io Moth, Polyphemus Moth, Canadian Tiger Swallowtail. OSMETERIA : Canadian Tiger Swallowtail. CARAPACE/PLASTRON : Spotted Turtle, Blandings turtle. NACRE : Eastern Ellipso, Brown-lipped snail (Mollusks). APOSEMATISM : Monarch, Oleander aphid, Red Milkweed Beetle, Red Eft, Dogbane Tiger Moth. MULLERIAN MIMICRY : Bees and Wasps (Hymenoptera). BATESIAN MIMICRY : Hover fly, Locust borer, Bee mimic flower beetle. TRICHOMES : Great Mullein, Stinging Nettle. PHYTOLITHS : Souringrush horsetail, Grasses. RAPHIDES : Skunk Cabbage. SECONDARY METABOLITES : Red Oaks (Tannins), Prickly ash (Limonene), Eastern Red Cedar (Cedrol). HYPERPHAGIA : Yellow-rumped warbler, Semipalmated sandpiper. ZUGUNRUHE : Red Eye Vireo, Red-winged Blackbird. ECDYSIS / ECDYSONE : Process of molting; hormone mimicked by Phytoecdysone in Bracken Fern. ENDOTHERM : Black-capped Chickadee, American Goldfinch, River Otter, Beaver, Raccoon, White-tailed deer. ●​ ●​ ●​ ●​ ●​ ●​ ECTOTHERM : Fish, Amphibians, Insects. PELLAGE : River Otter, Beaver, Muskrat (Guard hairs and Underfur). SUBNIVEAN ZONE : Mice, Voles, Shrews. SCATTER HOARDING : Black-capped Chickadee, Grey Squirrel. LARDER HOARDING : Red Squirrel, Short-tailed Shrew, Beaver. BLARINATOXIN : Short-tailed Shrew (venomous saliva). The staggering diversity of strategies detailed in this compendium illustrates the profound interconnectedness of form and function. Every physical structure and every behavioral instinct is a refined solution to the relentless challenges of predation, environmental extremes, and the biological mandate for survival.