BIOL 1902 Notes // Lectures 1-8 PDF

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LECTURE 1 // September 5, 2018    Natural History is…   The enjoyment of nature and the forming of appreciation and respect on living things  ❖ Living, breathing, dynamic plants and animals  This is the REAL world, it is the ONLY and longest running reality show. No sec...

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LECTURE 1 // September 5, 2018  Natural History is… The enjoyment of nature and the forming of appreciation and respect on living things ❖ Living, breathing, dynamic plants and animals This is the REAL world, it is the ONLY and longest running reality show. No second takes! ❖ Learn to be in the now of nature ❖ Learn new things about them, how to call them Observational Science ❖ The OBSERVATION and the interaction of plants and animals - flora and fauna Someone that is interested in natural history is a NATURALIST. Natural History: dealing with the properties of natural objects, plants or animals; a scientific account of any subject on similar lines  Extra Info Herps: Reptiles and amphibians for short Plants can exploit animals just as easily as predators and prey. ❖ For ex. Orchids lure male insects with smells and colours resembling potential mate while others create the fake promise of food Parental care of animals. Parasitoid: An insect whose larvae live as parasites that eventually kill their hosts Mutualism: b  oth partners benefiting, animal partnership ❖ For ex. Bird pecks flies off of cows eyes. Bird Banding: A  tag on the leg of a bird for individual identification  How Animals Survive? ❖ Defences ❖ Appearances - C  amouflage: to blend into the surroundings to survive and reproduce = CONCEALMENT: a method of cryptic  (hiding but not moving), which is used to avoid observation or detection by other organisms ❖ Ex. Moth and trees, stink bugs and leaf ❖ All of these examples of survival overlap.  Types of Camouflage Camouflage is used to mask: ❖ Location ❖ Identity ❖ Movement from prey ❖ Protection from predators ❖ Camouflage does NOT work when one is not cryptic. ➢ The animal must be still and not moving. 

1. Background Matching: T  o avoid recognition the body has the same colour, form or movement as the environment around them. ❖ In different settings/habitats such as vegetation, there are specific styles to background match ➢ Meadows, grasslands, marshes ■ Dominant feature: vertical stripes, long, thin lines ■ Ex. AMERICAN BITTERN, Sparrows, Cattail Marsh ➢ Dabbled pattern floors ■ Dominant feature: patches of light and dark ■ Ex. RUFFED AND SPRUCE GROUSE (ground nesting bird) = they use both background matching and cryptic (so does the Eastern Screech Owl). Fawns have spots to camouflage the forest floors.  2. Disruptive Patterns: P  atterns that break up the general form of an animal making it hard to be recognized. Different parts of the body combining together to create one pattern. ❖ EYE LINES AND EYE STRIPES of songbirds ➢ Especially important when sitting on nests ❖ CHIN STRAPS on Canada goose ➢ Used to conceal themselves, breaks head from ground ❖ BREAST BANDS on HORN LARKS AND KILDEER ❖ NECKLACE on loons ➢ When they feel disrupted, they can lay down ❖ STRIPES AND LINES ON THE BACK AND FACE of chipmunks Coincident/Continuous Disruptive Colouration ❖ BROWN AND GREEN SPOTS AND STRIPES on leopard frogs ➢ When the legs of the frogs are folded in, there are dark bands that continue and join together  3. Seasonal Colour Change: Changes of colours to match/adapt to the setting of the season. ❖ GRAY TREE FROG: camouflages by changing its colour depending on its background. ➢ In the winter they are able to survive while half of its body turns to water and freezes. ➢ They hide in the morning and feed at night. ➢ Bark mimicry is also used. ❖ SNOWSHOE HARES / VARYING HARES: change from brown to white for the winter. 

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LECTURE 2 // September 10, 2018  MASQUERADE VS. BACKGROUND MATCHING: In BM, the animal’s colour and patterns match the background whereas M is having the shape of the specific thing they are mimicking or a part of the body is modified to match the environment.  4. Masquerade/Mimicking: Organism resembles inedible and generally inanimate objects. Changing appearance to match the environment. ❖ Bark mimic: Resembling bark on a tree ➢ GRAY TREE FROG ❖ Dead leaf mimicry: Resembling dead leaves ➢ Moths, Easter Comma, Morning Cloak ➢ ANGLE-WINGED BUTTERFLY shape their body ❖ Live leaf mimicry: Resembling live leaves ➢ Katydid ➢ LUNA MOTHS hide up high in trees in daytime to blend in ❖ Twig mimic: Resembling twigs ➢ INCHWORM ➢ WALKING STICK ❖ Thorn mimic: Resembling thorns on twigs, will normally stay very still on plants while they suck out juices from the plant. ➢ TREEHOPPERS ❖ Bird dropping mimicry: r esembling bird dropping, animals will tend to not eat ➢ GIANT SWALLOWTAIL CATERPILLARS have a shiny finish to them unlike other insects that have a matte finish Some animals use their surroundings and put the surroundings on themselves for camouflage. ❖ Camouflaged Loopers: use the surroundings (such as plants) to cover their body, hiding them from predators ➢ SPITTLE BUGS generate a frothy wet spit-like material called spittle  to hide themselves in from predators ➢ WOOLY APHIDS create silk strains on top of themselves to conceal ➢ SCARLET LILY LEAF BEETLES LARVAE (child form) coats itself with feces to conceal itself  In muddy areas and in poop, butterflies or moths use puddling  to get nutrients such as salts, sugars and proteins that flowers don’t have. Their pattern of disruption as a group combined mimic an image of a snake.   5. Bicoloured Camouflage: H  aving a tow-toned body, usually dark above and light belo, often seen on animals living near the surface of ponds. Allows for background matching from two directions.

❖ WHIRLIGIGS BEETLES have a black above and white below. They look like sunshine on top from predators below and look like water from predators above. ❖ BACKSWIMMERS have a white top and black bottom, upside down swimmers to get the same defence as the Whirligigs. Countershading and self shadow concealment: using bicolouration to appear flat and blend in the background during sunshine (sun creating a shadow that casts down on the belly). ❖ WHITE TAILED DEER are dark above and light below, this helps them be in the open areas and appear flat during sunshine to blend into their background  When camouflage and cryptic behaviour fails, some animals have a second defence or a “Plan B”.  Startle Patterns Patterns shown to predators when camouflage fails, to startle the predator and allow time for escape. ❖ UNDERWING MOTHS have bright colours underneath their wings, when they open up ❖ GRAY TREE FROGS have bright yellowed spots flashed when they leap ❖ Red-bellied snake - bright orange belly Hidden Eyespots: Having startle patterns in the shape of eyes to scare the predator. ❖ POLYPHEMUS MOTH ❖ SPHINX MOTH Startle Structure: A  startle part that comes out to startle. ❖ GIANT SWALLOWTAIL CATERPILLARS when touched on the head, will pop out bright red coloured horns (called Osmeterium) that resembles a snake’s tongue. Startle Sound: A  sound released to startle the predator. ❖ BEAVERS use their tail to slap the water ❖ RUFFED GROUSE take off with an explosive sound caused by their wings to startle. ❖ MORNING DOVES Distraction Patterns: Patterns that serve to distract a predator’s attention to a non-vital body part. ❖ TIGER SWALLOWTAIL BUTTERFLIES have a tiny thick antenna tail to deflect the attack ➢ GIANT SWALLOWTAILS ➢ HAIRSTREAK ❖ Others have fake heads. Deflection Patterns: Patterns that serve to distract a predator’s attention to a non-vital body part but this body part is autotomic. ❖ Autotomy: Having body parts that can be discarded and grown back.

❖ FIVE LINED SKINKS have tails that disconnect upon contact and move around a few seconds to distract the predator, allowing the Skink to escape (the tails grow back but not as long)  Permanent/Visible Eyespots To trick the predators to believe the animals are bigger than they are. Not a startle pattern. ❖ EYE ELATER (BEETLE), TIGER SWALLOWTAIL CATERPILLAR  LECTURE 3 // September 12, 2018  Body Armour For defense making it hard to bite into them. No defence is perfect because if they were, all the animals would be able to adapt to them, then nothing would survive.   Physical Defenses: The first line of defence (or outside defence system) includes physical barriers that are always ready and prepared to defend the body from infection. Hard Defences Hard exoskeleton: ❖ TURTLES all have a hard outer shell to protect them from predators ➢ BLANDING TURTLE has a carapace top and plastron bottom, they can partially close their shell like a bridge ➢ BOX TURTLES can close their shell completely ■ They have had their body armour for millions of years, it has evolved barely ➢ SNAPPING TURTLES snap (attack) for defence, they can not pull themselves back into their shell ■ One of the oldest turtles Internal skeleton: ❖ MILLIPEDES made of chitin ❖ CLICK BEETLES have a very hard outer shell ❖ SNAILS and CLAMS have hard shells made from Calcium  (strong) Soft Defences ❖ Soft hairs i s a defense having the body covered in hair ➢ EASTERN TENT CATERPILLARS form silk webs around leaves and feed inside them, the silk tent is used for protection ➢ FALL WEBWORM also makes silk tents, they have leaves inside ❖ Hard hairs (modified hairs) are hairs that translate into hard spines. Hair can be modified into stiff spines, offers more protection because they’re painful inside the predator’s mouth. ➢ WOOLY BEARS have stiffer spines for hair

➢ GYPSY MOTH CATERPILLAR and TUSSOCK MOTH CATERPILLAR uses their hairs as a defence against birds, when under attack they roll into balls ❖ Body hairs (Guard hairs) a  re like modified quills. ➢ PORCUPINES ■ They don’t face the attacker and can’t shoot their hairs ■ Once it penetrates something, the quill comes right out ■ Antibiotics in quills ● If They fall and get impaled by their own quills, they can heal themselves ■ Gives visual warnings first: raise their tail, chatter teeth, warning odour from skin above base of tail  Chemical Defenses: Attacks found by releasing chemical agents. ❖ IO MOTH CATERPILLAR have poison  spines (hair and poison) ❖ Aposematic colouration (Warning colouration): H  aving bright coloured colouration to warn predators that the animal is poisonous which allows them to remember these distinctive colours to avoid eating these in the future. ➢ BLACK AND WHITE, APOSEMATIC AT NIGHT. ➢ COLOUR IN THE DAY, BETTER STAY AWAY. ➢ GIANT LEOPARD MOTH CATERPILLAR when endangered will roll up and expose its poisonous brightly coloured spines ■ Spines inject chemicals that burn ➢ Anything with milkweed ■ MILKWEED TUSSOCK MOTH CATERPILLAR ■ MILKWEED BEETLE ➢ YELLOW JACKET WASP is bright yellow ➢ RED EFT has poisonous skin ➢ STRIPED SKUNK the stripes work at night ❖ Sequestering (to take): A  ttaining chemicals (poison) from plants or other animals. Acquired in diet and then stored in the body. ➢ From plants ■ MONARCH BUTTERFLY CATERPILLAR eats Milkweed Leaves containing cardiac  glycosides (terpenoids) and  then stored. ■ BLACK SWALLOWTAIL CATERPILLARS gets poison from Water Hemlock ➢ From animals ■ LADYBUGS create their own poison from plants ■ PHOTINUS FIREFLIES (BEETLES) sequester Steroidal Toxins ■ FEMALE PHOTINUS FIREFLIES get their poison from eating MALE PHOTINUS FIREFLIES ● The process of them getting the males is called A  ggressive mimicry.  Lighting up their abdomens, these beetles mimic

the mating signals of other female firefly species, acting as just another single beetle looking for love. When a male firefly responds, they travel over thinking of mating. Unfortunately, the female firefly just wants to eat. ❖ Chemical defences can be released from different parts of the body. ➢ Skin: RED EFT and AMERICAN TOAD ➢ Mouth: GRASSHOPPERS and SAWFLY LARVAE ➢ Legs: BLISTER BEETLES (Cantharidin (a terpenoid) released from leg joints) ➢ Stingers: YELLOWJACKET PAPER WASPS and HONEYBEES (but they have a one time use) ➢ Osmetaria: SWALLOWTAIL BUTTERFLIES ➢ Anal: SKUNK (sprays Sulfur alcohol, they’ll give a warning first) ➢ BOMBARDIER BEETLE uses a chemical defence that sprays out hot quinone gas, burns and makes a loud pop  Animals are equipped with chemical defences often have aposematic colouration. Aposematic colouration allows a predator to learn and avoid that colour pattern. Typically found in insects and some reptiles, not in birds.  Mullerian Mimicry Copying the colouration of animals that are dangerous or poisonous w  hile being dangerous and poisonous yourself. ❖ MILKWEED BEETLE and MILKWEED BUG have warning colouration (brightly red and black). ❖ WASPS and BUMBLEBEES ❖ MONARCH CATERPILLAR sequesters poison from milkweeds ❖ VICEROY BUTTERFLIES and MONARCH BUTTERFLY  Batesian Mimicry Copying the colouration of animals that are dangerous or poisonous while not being dangerous and poisonous yourself. ❖ A model (being mimicked) and  a mimic (mimicking), number of models > number of mimics. ❖ Models and mimics must occur at the same time of year. ❖ HOVERFLY (mimic) and BUMBLE BEES/WASPS/HONEY BEES/BALD-FACED HORNETS ➢ Stinging insects have 2 sets of wings, flies have 1 ➢ Wasps have many mimics ❖ SUGAR MAPLE BORER BEETLE looks like YELLOW JACKET WASPS ❖ Note: Drinking a bad glass of milk, will drink again but yea.  

Automimicry The fact that animals of the same species resemble each other. The benefit of this is so predators that have had a negative experience by eating one of the species, will not go after the others. ❖ Ex. All the yellow bees.

 LECTURE 4 // September 17, 2018  Behavioural Defences Not all animals have warning colorations to show that their toxic. ❖ American toads have the toxin Bufotenin  in skin glands and they also bluff. ❖ Bluffing: Animals inflate themselves to look larger. ➢ HOG-NOSE SNAKES puffs up to scare ❖ Thanatosis: Playing dead to avoid predators that want to kill them not eat them. ➢ HOG-NOSE SNAKES doesn’t want to be stomped on ➢ BLISTER BEETLES ➢ VIRGINIA POSSUMS  Behavioural Group Defence Getting in groups for protection. Safety in numbers. Better odds of surviving. More eyes to watch for danger. Visual confusion. ❖ Yarding: In the winter, WHITE TAILED DEERS (group of deer = yard) ➢ Some can have 1o0 - 1,000 in a group ❖ Flocking: G  roup of birds ➢ Used to confuse predators ➢ Lower chances of being caught ❖ Group Defence in Social Insects: L  ive as a group and share responsibilities ➢ Ex. ANTS  Aggressive Group Defences: ❖ YELLOWJACKET WASPS (SOCIAL WASPS) ➢ Attack Pheromones: when one is alarmed, release the pheromone, calls in the troops, sting the attacker together ❖ Mobbing: Smaller birds attack bigger birds, attack and then call for more birds of the same pack. ❖ Pre-emptive (happens before the attack occurs) defence  : The small birds attack the owl before the night time, when they head to sleep and the owl comes to eat them ❖ Bodyguards: A  PHIDS have CARPENTER ANTS as guards to protect them in exchange for sap ➢ Oleander aphids don’t have bodyguards because they are on milkweed 

Behavioural Defences That Are Odd ❖ White Flags: EASTERN COTTONTAIL AND WHITE TAILED DEER ➢ The white tail is prominently displayed ➢ They show the white flag to show a deflection pattern, they could also show that “hi i’m here im advertising awareness, why bother get me i’m running away!” ➢ Predator will stare at tail and trip (distraction) ■ Wolves only succeed to get a deer 10% of the time  Vigilance: Animals being alert and looking out for danger. Scanning the environment for danger. 1. Auditory (Sound/Ears) ❖ Large ears (external pinnae) capture sound ❖ Ears pivot  to scan all directions without moving head ❖ RABBITS and DEER have huge ears ❖ BEAVERS have small ears because they swim ➢ Some animals can’t have big ears because of what they do. ❖ TIGER MOTHS also have “ears” = membranes on the body thorax that pick up vibrations. ➢ They detect bat calls to escape by diving to the ground ❖ LACEWINGS have ears on the base of their wings ❖ SNAKES have no ears but sense vibrations from the ground ➢ Enhanced power of smell/taste with their tongues ➢ The tongues (4) grab the chemicals out the air brings it into their double chamber mouth and if they can sense more on one side, that’s where the danger is ➢ They also use it for food ➢ Scents are analyzed in the roof of their mouths called the Jacobson’s Organ 2. Olfactory (Smell/Nose) ❖ Animals have Jacobson’s Organ in their snouts which are sensory cells ❖ Flemen: The posture assumed by animals to expose their Jacobson’s Organ ❖ MOOSE have enlarged snouts ❖ FOXES and DEER do too 3. Visual (Sight/Eyes) Eye placement is affected by other aspects of an animal's natural history. ❖ Hunted: E  ye placement on the side of head to have total field view ➢ Can better see the world without movie head ➢ Less ability for depth perception ➢ 360° view , wider view ➢ Ex. SNOWSHOE HARE and MALLARD (DUCK) ❖ Hunter: E  ye placement on the front of the face

➢ Eyes are in front and overlap which is called binocular vision which gives superior depth perception ➢ Eyes at the front, help you hunt. ➢ Ex. OWL, FOX and AMERICAN WOODCOCK ❖ BEAVER eyes are near the top of their head and the ears and nose are all lined up over the water so that they can use all their sensory and protect itself on the water ❖ SANDPIPERS have eyes placed high in their head because they stick their mouth in the ground for food and need to look out for predators ❖ Bigger the eye, more light it gathers. ❖ Rods: Low light/black and white detection ➢ Active night animals have more rods and larger eyes. ❖ Nocturnal animals display eyeshine due to the layer of reflective cells on the retina - Tapetum  lucidum ❖ Cones are for the sharp, daylight. ❖ Different colours for different eyeshines ❖ More eyes allows for more complete vigilante - yards and flocks 4. Two Different Flocks ❖ Single species: ➢ Ex. WAXWINGS and SANDPIPER ➢ Same food, same type ❖ Mixed species: ➢ More than one species ➢ More scattered and variety of food which offers more eyes to detect danger around them ➢ Ex.WARBLER ❖ Single species flocks fly for food in large quantities so that the whole flock can eat without competing for food ❖ Mixed species flocks extract different resources found in small quantities, little competition 5. Pressure Sensors ❖ SNAKES: have no external ears, but sense vibrations from the ground ❖ FISH: have the lateral lines on their side and can sense pressure  LECTURE 5 // September 19, 2018  Plant Defences Plants encounter the same problems as animals. Every part of the plant is eaten.  Damaged Plant means that a plant has lost a battle. Healthy Plant means that the plant has not yet lost a battle.  Bark Beetles: L  ay eggs in wood and eventually grow and exit through bark

 Physical Defences Constitutive Defenses a  re defences that are always present. Induced Defences are defences that are NOT always present.  1. Hard Armour ❖ These have a dual function of support and protection. ❖ BARK - Trees and woody plants have external armour ❖ Seeds ❖ Acorns have extremely tough coats ❖ Just like a turtle’s shell 2. Sharp Spines ❖ Producing objects that pierce ❖ MODIFIED LEAVES ➢ Ex. SCOTCH THISTLES 3. Prickles ❖ Comes from the skin of the plant ❖ Epidermal outgrowths like hairs ❖ Epidermal cells create the prickle ❖ Ex. BLACKBERRIES AND RASPBERRIES 4. Thorns ❖ Modified branches ❖ Ex. HONEY LOCUST (trees with thorns) ❖ When thorns are broken off you can see that the tissue goes deeper into the plant, whereas pricks are just on the surface ❖ THISTLES are protected by thorns and that’s why cows stay away from them  Not all physical defenses have to be hard. For example, RAGWEEDS cause allergies.  Trichomes ❖ Soft hairs on the plant that only protect from small animals making it harder for them to climb or eat the leaves. ❖ Physical and chemical glands, not poisonous ❖ Ex. RAG...