Study Guides (238,455)
Canada (115,142)
Biology (180)
BIOL 1902 (60)


60 Pages
Unlock Document

Carleton University
BIOL 1902
Michael Runtz

BIOL 1902 – Natural History Introduction Natural History → the observation of living plants and animals – flora and fauna – and their interaction. It is an observational science. Someone with an interest in Natural History is a naturalist. Famous Naturalists 1. Linnaeus – Set the foundation for binomial nomenclature. 2. Charles Darwin – “world’s most famous” naturalist 3. John James Audubon – one of the world’s first “bird watchers” 4. Ernest Thompson Seton – semi-famous Canadian naturalist 5. Roger Tory Peterson – bird and nature field guides Adaptations - features or traits that offer plants and animals an advantage in solving problems. They are not acts of intelligence or planned solutions. They are features that have taken thousands or millions of years to evolve. - adaptations arise because of selective pressures. - adaptations can be physical, chemical, physiological, or behavioural → Selective pressures are a force of natural selection that acts on animals and plants, removing those that are less fit from the gene pool and selecting for traits that enhance survival or reproduction. → Abiotic pressures – pertaining to entities that are not biotic, such as wind or temperature. → Biotic pressures – pertaining to a living organism, such as an animal, plant, or bacterium. → natural selection – the driving force behind evolution; comprises many selective pressures including environmental extremes (abiotic pressures) and the selective power of plants and other animals. (biotic pressures) for example female mate choice, parasitism and predation. - the natural selection of adaptations are what drive evolution. Genetic Survival - genetic survival is the key to life – it is immortality. - all living things are driven to reproduce, and any trait that gives a plant or animal an advantage in reproduction or passing on genes can proliferate and become the trait we see today. Staying Alive (Textbook Chapter 1) Defences Physical Defences Camouflage / concealment → camouflage – colour, form, and possibly movement, that render an animal difficult to detect or recognize → concealment – avoidance of detection or recognition through the employment of camouflage → crypsis – the avoidance of detection by combining motionless behaviour with some form of camouflage (i.e. background matching) • Crypsis examples – Eastern Whip-Poor-Wills, American Woodcock - two common forms of camouflage or concealment 1 - Background Matching 2 - Disruptive colourization Background Matching → background matching – having an appearance that matches the general colour, contrast, and pattern of the local environment • Background matching examples – most ground nesting birds (earth tone dappled spots), American Bittern (vertical lines, points head up – like cattails), Gray Tree frog (changes colour to match surroundings), Snowshoe Hair (changes colour seasonally), Wood Thrushes (pale breasts with dark spots), deer fawn (brown coat, white spots). Disruptive colourization → disruptive colourization – a type of camouflage in which patterns create the visual illusion of false edges or boundaries, thereby breaking up the visual outline of an animal and rendering it unrecognizable. • Disruptive colourization examples – Killdeer (breast bands that are obvious when it’s standing but effective when it’s nesting), Canada Goose (chinstrap that works best when the head is lowered), Common Loon (coloured necklace), American Bittern and female Red-Winged Blackbird (vertical stripes along neck), Savannah Sparrow (Brown stripes on pale breast match vertical lines in grass habitat) → coincident disruptive patterns – a type of camouflage in which disruptive colouration on different body parts align in certain postures to create a continuous disruptive pattern • Coincident disruptive pattern examples - Leopard Frog (when sitting patterns on limbs and body match up to create a larger pattern) - supercilium – a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head. (supercilium examples – Chipping Sparrow) - eyeline – a distinctive line across the head of the bird through the eye (eyeline example – Chipping Sparrow) Masquerade → masquerade – a form of camouflage in which an animal’s body is shaped like a piece of its environment (i.e. twig) or something inedible (i.e. bird faeces) • Masquerade examples – Angle Winged Butterfly (dead leaf mimic), Inchworm (twig mimic), Walking Stick insect (looks like a twig), Treehopper (thorn/bark mimic), Luna Moth (live leaf mimic), Giant Swollowtail Caterpillar and Viceroy Caterpillar (bird dropping mimic) Bicolouration → bicolouration – a form of camouflage in which one surface is dark and the other is light, allowing background matching from two visual perspectives; generally a trait of small animals inhabiting the surface of aquatic habitats • Bicolouration examples – Whirligig Beatles (white on bottom, black on top), Notonectidae also called Backswimmers (black on bottom, white on top, swim on their backs) → countershading – a type of camouflage in which the lower parts of a body are lighter than the upper parts to offset the three-dimensional effect of shade by creating a uniform or flat appearance; also called self-shadow concealment or obliterative shading • Countershading examples – White Tail Deer (white belly to hide shadows) Startle Patterns Colourful patterns → startle patterns – bold and often colourful patterns that are exposed suddenly to startle a predator; sometimes serve a deflection or distraction role. - startle patterns are usually hidden until needed • Startle pattern examples – Underwing Moths (genus: Catacola – beautiful behind – they have colourful underwings), Gray Tree Frog (yellow under legs), Ring-necked Snake (yellow belly), Giant Swallowtail Caterpillar (osmeterium) → osmeterium (osmeteria, plural) – an eversible gland in the head of swallowtail caterpillars that, when extruded, resembles a snake’s tongue and emits a foul odour. Large conspicuous eye spots → eyespots – round patterns that look like eyes; often used as startle patterns or to make an animal look like a larger species. • Eyespot examples – Sphinx Moths (eyespots), Eyed Elaters and Eastern Tiger Swallowtails (large fake eyes to appear as larger animals) Deflection / distraction features → deflection patterns (distraction patterns) – patterns that direct a predator’s attack to a non-vital part of an animal’s body; some deflection patterns first serve as a startle pattern. → deflection structure – a structure on a non-vital part of an animal’s body that directs a predator’s attack to it. → autotomy – in animals, the shedding of a limb that usually, but not always, grows back; self-amputation • Deflection examples – Swallowtail moths, Eastern Tailed Blue Butterfly (tails that look like antennae with eye spots on the back look like heads), Five-lined Skink (blue tail detaches, grows back smaller, autotomy), Crane Fly (legs detach easily, do not grow back, autotomy) Constructed camouflage structures • Constructed camouflage examples - Spittle Bug (hides in foamy spit it excretes), Woolly Aphids (hides in fuzzy mould-like webs), Leaf Roller (uses silk to roll a leaf and hides in it), Sumac Gall Aphids (hide in plant swellings), Caddis Fly larvae (create little houses of debris on the bottom of aquatic habitats.) Protective structures Body armour • Body armour examples – Millipede (coils up exposing hard exoskeleton), clams and snails (calcium protective shell), beetles (hard backs with grooves to tuck in legs and antennae), turtles (Box Turtle can completely close shell, Blanding’s turtle can partly close shell because of a hinge on their anterior, Snapping Turtles defend themselves aggressively; they cannot withdraw into their shells for protection) Constructed enclosures • Constructed enclosures examples – Eastern Tent Caterpillar (live in groups. Construct a big tent, exit tent at night to feed), Fall Webworms (construct a tent that includes their food source) Hair/fuzz → guard hairs – the longer, coarser hairs that make up the outer coat or pelage of a mammal • Hair/fuzz examples – Gypsy Moth Caterpillar, Tussock Moth Caterpillar (hairy, roll in to a ball when threatened to protect underside), Woolly Bear Caterpillar (stiff, spine-like hairs), Porcupine (quills are modified guard hairs, quills have antibiotics on them in case of self-impale accidents) - Black-billed Cuckoos and Yellow-billed Cuckoos eat fuzzy caterpillars; fuzz is removed in their crop, oesophageal pouch, and then coughed out. Chemical Defences → aposematic colouration – bright colours that warn of a strong defence; also called warning colourization → inducible defence – a defence that is only present when a plant or animal is under attack → sequester – obtain from another source; usually achieved by eating something not manufactured by the sequestering animal (i.e. poison, toxins) → terpenoid – a group of important plant chemicals that lack nitrogen used primarily for metabolic functions and secondarily for defence (sequestered by some animals for chemical defence) Toxic hair / spines - hairs + poison = poison spines • toxic hair / spines examples – Monkey Slug, Io Moth Caterpillar Bad taste / poisonous → alkaloids - bitter tasting nitrogenous chemical compounds used for defence • Bad Taste examples – Milkweed Beetles, Milkweed Bugs (orange/black aposematic colouration), Lady Beetles (make their own alkaloids) Exuded poison / spray / sting → cardenolide (cardiac glycoside) – a type of terpenoid used as a chemical deterrent that, in large doses, acts as a heart poison → cantharidin – a type of terpenoid typically used as a chemical defence by Blister Beetles • Exuded Poison Examples – Red Eft Newt (poison skin), wasps and bees (stingers), skunk (sulphur alcohol spray, black and white nighttime aposematic colouration), Monarch Butterfly Caterpillar (sequesters cardiac glycoside from milkweed), Sawfly Larvae (poison bubbles out of the mouth), Blister Beetles (Spanish fly (cantharidin) comes out leg joints), Dytiscid Water Beetles (chemicals shoot out anus) Mimicry → mimicry - whereby an animal takes on the appearance of something else (i.e. an inanimate object such as a piece of bark or leaf; another animal, one often aposematically coloured) Müllerian mimicry → Müllerian mimicry – whereby two or more animals (i.e. Milkweed Beetles and Milkweed Bugs) share similar appearances and each honestly advertises some form of defence • Müllerian mimicry example – bees and wasps Batesian mimicry → Batesian mimicry – whereby a harmless animal, the mimic, resembles (behaves, looks or sounds like) another animal, the model, that is toxic or otherwise well defended → model – in Batesian mimicry, the well-defended and usually aposematically-coloured animal that the harmless mimic resembles (behaves, looks or sounds like) - the success of Batesian mimicry depends on there being more numerous models than mimics. • Batesian mimicry examples – Monarch Butterfly and Viceroy Butterfly – bees and wasps and a bunch of different types of Hoverflies that look like them. Behavioural Defences Aggressive mimicry → aggressive mimicry – whereby an animal uses behaviour or appearance (i.e. a modified body part) to resemble an edible item or harmless animal for the purpose of deceiving prey • Aggressive mimicry examples – Photuris Fireflies (fireflies are beetles) females eat Photinus Fireflies after attracting them with mating blink signals, sequesters steroidal toxins from the males. Thanatosis → thanatosis – feign death • thanatosis examples – Hog-nosed Snake (puffs up to look big, if that fails, play dead), Blister Beetle, Opossum Flocking / schooling / yarding → communal roost – a site in which a large number of birds gathers to spend the night. (Communal roost examples – Rock Pigeons, Red-winged Blackbirds, Turkey Vultures) → single-species flock – a flock of birds consisting of only one species → mixed species flock – a flock of birds comprising more than one species; often formed in migration or in winter to provide enhanced vigilance. → deeryard – an area where White-tailed Deer gather for the winter; often lowland dominated by Eastern White Cedars - birds flock, fish school, deer yard Social Insects – Group defence - pheromones summon other insects in the hive/nest to join the attack Mobbing – Pre-emptive defence → mobbing – a defensive response in which animals (birds usually) noisily harass a potential predator → pre-emptive defence – in reference to mobbing, a behavioural defence that may serve to drive away a predator before it has a chance to attack → locatable alarm call (locatable distress call) – an avian alarm call with a low frequency and acoustic qualities that allow other animals to easily locate the caller; often used in conjunction with distraction displays, or with mobbing Distraction or warning behaviours - some animals raise a white tail or otherwise indicate to predators that they have been detected. Others hiss, stamp their feet, emit other warning sounds or posture to try to look larger • examples – white tail deer (tail goes up, deer runs), Cottontail (white tail) Enlisting help for defence - Woolly Aphids, Froghopper, Treehopper excrete sugar-rich drops that attract Carpenter Ants. The ants defend their “herds” from predators and harvest these drops. Vigilance Pressure sensitivity → lateral lines – on the sides of fish and some aquatic amphibians, a row of special sensors (neuromasts) that are sensitive to pressure changes and possibly electromagnetic fields (at least in sharks) - snakes can sense vibration along the ground for location detection Olfactory Vigilance → olfactory – of or pertaining to the sense of smell → Jacobson’s organ – a sensory organ for enhanced detection and analysis of airborne scents usually located in the palate of an animal’s mouth; also called vomeronasal organ • Olfactory Vigilance examples – Moose (large surface area in nasal passages means better sense of smell, also has Jacobson’s organ), Snakes (“taste” smells in the air, tongue is forked so the smell direction can be determined), Auditory Vigilance → tympanum – the membrane associated with hearing in frogs and many insects • Auditory Vigilance examples – Tiger Moth (tympanum to hear bats, clicks aposematic back at bats because they are poisonous), Mantid (tympanum). Moose (big ears, also known as pinnae , independent swivel) Visual Vigilance → tapetum lucidum – in the retina of night-active animals, a layer of cells that reflects unused light outward toward the receptor cells; produces eyeshine - eye placement on head can increase field of view. More visual overlap increases depth perception in that area but decreases overall field of view. - eye construction. Cones see colours. Each cone has a nerve connection. Cones are used when light is ample. Rods see brightness. Many rods share a nerve connection. Rods are used in low light. - most prey animals have eyes on the sides of the head to watch for predators. most predators have eyes on the front of the head to increase depth perception and visual acuity. • Visual vigilance examples – American Woodcock (eyes placed near back of head, can see when beak down in mud to feed), American Bittern (eyes placed near beak so it can see when head up in alert posture), Flying Squirrel (nocturnal animal, has big eyes) Fighting Back (Textbook Chapter 6) - plants are always under attack Physical Defences - Aposematic colouration happens in plants → automimicry – whereby one part of an organism resembles a different part of the same organism - New buds may resemble prickles, this is automimicry External Protective outgrowths Spine → spine – a sharp highly lignified, non-living protective structure derived from a modified leaf or part of a leaf • Spine Examples - Scotch Thistle (spines) Prickle → prickle – a sharp, protective outgrowth of the epidermis; a modified trichome • Prickle Examples - Prickly Ash (prickles) Thorn → thorn – a sharp, protective outgrowth derived from a modified branch of a plant • Thorn examples - Hawthorn (thorns), Honey Locust (thorns) Internal Protective structures Trichomes → trichomes – a plant defensive hair, often clubbed; can be non-glandular or glandular - glandular trichomes – contain volatile oils and other secretions produced by the plant for defence • Trichome examples – Ragweed (trichomes), Mullein Leaves (trichomes), Stinging Nettles (glandular trichomes), Water Smartweed (inducible trichomes if the water goes away) Digestibility reducers → digestibility reducers – a compound that makes cell walls and other plant tissues difficult to digest (i.e. the structural elements cellulose and lignin), or that binds to digestive proteins in an animal’s gut rendering them ineffective (i.e. tannins) Plant Cell Construction → cellulose – a structural element in cell walls that is also a digestibility reducer; most plants are about one third cellulose → hemicellulose – a binding agent that holds cellulose bundles together in plant cell walls → pectin – a binding agent that holds cellulose bundles together in plant cell walls - microfibrils – strands of cellulose that are bound in small bundles - fibrils – larger bundles of cellulose microfibrils → silica – silicon dioxide; a structural component of tissues especially common in horsetails and grasses → phytoliths – discrete bodies of silica in the tissues of plants; also called plant opals or silica cells → cutin – a waxy compound that is one of the main components of cuticle that is hard to digest for animals. Sclerified structures → sclerified – tissues hardened by the addition of sclereids → sclereid – a sclerenchyma cell (usually dead) that is rigid and heavily fortified with lignin often present in large numbers in seed coats and pits; sometimes called “stone cells” → lignin – a chemical compound, the main focus of which is to provide support to woody tissues Chemical Defences → constitutive defence – a plant defence that is always present in its active form → inducible defence – a defence that is only present when a plant is under attack Secondary Metabolite → secondary metabolite – a plant compound that does not play any role in cellular activity; often serves to attract pollinators or deter herbivores → tannin – the most common secondary metabolite in plants; serves a defensive role as a feeding deterrent and as a toxin; particularly abundant in coniferous trees and oak leaves. tannin is an astringent. → astringent – a chemical compound that constricts tissues, usually by drying them out → idioblast – a cell in which minerals, lignin or other abiotic substances are housed (like calcium oxalate) - calcium oxalate crystals (caustic) form in some plants • Secondary Metabolite examples - Arum (calcium oxalate crystals), Milkweed (cardiac glycoside/terpenoids) non-nitrogen defences → terpenoid – a group of important plant chemicals that lack nitrogen used primarily for metabolic functions and secondarily for defence → cardenolide (cardiac glycoside) – a type of terpenoid used as a chemical deterrent that, in large doses, acts as a heart poison → oleoresin – a defensive sap rich in terpenoids produced by conifers and a few other plants (i.e. Poison Ivy); also called resin → urushiol – the reactive component in the oleoresin of Poison Ivy, Poison Oak, Poison Sumac - traumatic resin ducts - store extra oleoresin produced when plant detects an attack - some plants emit aposematic smells (mint) nitrogen based defences → alkaloids – bitter tasting nitrogenous chemical compounds used for defence. A family of thousands of chemicals • Alkaolids examples – Asters (alkaloids), Buttercup (alkaloids) - types of alkaloids → lupine alkaloids (also called quinolizidines) – have a strong repellent and toxic effect on molluscs, insects, and mammals. → polyhydroxy alkaloids – interfere with insect digestive systems by binding with digestive proteins. → glucosinolates – a group of plant secondary metabolites that contain nitrogen. They are toxic to insects and mammals. Glucosinolates are common in Mustards with their characteristic smell. - hydrogen cyanide (HCN) also called prussic acid, is inducible (it would be poisonous to the plant otherwise) • Hydrogen cyanide examples – Ferns, Roses, Black Cherry, Bracken (chemically armed plant), Clover → laticifer – a compartment in leaves and stems that consists of one or more elongated secretory cells in which defensive compounds such as latex are stored Phytohormones → phytohormone – a hormone produced by plants - phyto proteins – distrupt digestion - phyto amino acids – causes deformities → phytoecdysone – a phytohormone that affects the moulting process in juvenile insects • Phytoecdysone examples – Rock Polypody, Bracken (fern, lots of phytoecdysones) → phytojuvenile hormone – a phytohormone that interferes with the maturation process in insect larvae • Phytojuvenile hormone – Balsam Fir (phytojuvenile hormone, oleoresin blisters) → phytoestrogen – a phytohormone that affects reproduction in female mammals • Phytoestrogen examples - Clover Phototoxins → phototoxin – a plant chemical compound that, once ingested, makes an animal more susceptible to damage from ultraviolet light; i.e. a furanocoumarin • Phototoxin example – St. John’s-wort (phototoxins) Command systems in plants → jasmonate acid – a phytohormone that regulates growth, and regulates defences against herbivore attack → ethylene – a gaseous organic compound, often released under abiotic or biotic stress, which triggers biochemical reactions in plants; the ripening of fruit is initiated by ethylene → salicylic acid – plays a critical signaling role in the activation of plant defense responses after pathogen attack • Salicylic acid examples – Poplar, Willow Trees Microbe Defences → necrotrophic pathogen – a microbe that kills plant cells before eating their contents → autophagy – the consumption by and within a cell of its own nutritional components; triggered by nutrient deficiency or necrotrophic pathogen attack - trees form compartments (compartmentalization) to block off attacks → phytoanticipin – constitutive anti-microbial chemical defences in plants. Inhibit development of microorganisms. Examples are saponin and a- tomatine → phytoalexins – inducible anti-microbial chemical defences in plants. Inhibit development of microorganisms. Examples are camalexin Calling For Help → extrafloral nectary – a nectary located on non-floral structures (i.e. stems and bracts); used to attract ants for protection, or insects for consumption by the plant → volatile organic compounds – an easily evaporated chemical compound; attracts pollinators to flowers, or animals such as parasitoids for defence Elemental Solutions (Chapter 2) Temperature Extremes Sub-zero → freeze avoidance – action taken to prevent internal body tissues from freezing in sub-zero temperatures; can be accomplished behaviourally (i.e. migration, descending beneath the frost line, etc.), or biochemically through the use of cryoprotectants (i.e. supercooling) Animal body temperature control methods (two) 1. → ectotherms – an animal whose internal body temperature is primarily controlled by the temperature of its surrounding environment. (cold blooded) (examples - insects, reptiles) 2. → endotherms – an animal whose internal temperature is primarily controlled by internal mechanisms (warm blooded) (examples – mammals, birds.) How animals deal with the cold (three) 1. → migration – an annual, two-way journey that is primarily a response to a predictable food shortage; often spans thousands of kilometres 2. → dormancy – a state of inactivity characterized by reduced metabolic activity and a drop in some or all of body temperature, heart rate, and respiratory rate lethargy, torpor, and hibernation are all types of dormancy 3. - Stay active Active endotherm strategies to combat cold Physical / physiological solutions Increase adipose tissue → adipose tissue – fat tissue of which there are two types, white (subcutaneous) and brown → subcutaneous fat – a white adipose tissue that is stored under the skin. - used in mammals for insulation (warmth) and used in birds as energy stores used for shivering thermogenesis. → shivering thermogenesis – the generation of heat by muscle shivering; an important strategy of birds in winter. → brown adipose tissue – a mitochondria-rich, high energy fat that is dark in colour and often stored near internal organs in dormant mammals. (when burned it gives more heat) Changes to fur/pelage and feathers → Gloger’s rule – the tendency for animals living in cool and arid northern regions to be paler than members of their species living farther south and in humid regions - colour of outer coat turns white because of less melanin pigment in the hair/feathers because they’re more hollow to allow for more air. (Gloger’s rule examples – Polar Bear, Arctic Fox, Arctic Hare, Snowy Owl, Rock Ptarmigan) - Dark hair and feathers absorb solar energy better but are not desirable in cold because they lose body heat readily in windy conditions. Pigmentation makes the structures denser, better for transmitting heat toward/away from the body. Darker feathers offer the advantage better resistance to bacteria in humid climates (not cold). - underfur – in mammals, a dense insulating coat of soft, fine fur that traps escaping body heat next to the skin; under guard hair. → contour feathers – the feathers that give a bird its form and general appearance; the outer layer of feathers that provide streamlining, insulation, and waterproofing. → down feathers – shaft-less, plumulaceous feathers that lie under the contour feathers of an adult bird or completely cover the skin of very young birds; their primary function is insulation. Changes to body composition → Allen’s rule – in colder climates, animals often have shorter limbs and smaller extremities. (Exception Example – Arctic Fox, bushy tail to wrap around face) → Bergmann’s rule – in a widely distributed group of animals, species with larger size and more rotund proportions will occur in colder regions (they have a smaller surface area to volume ratio) (examples – Woodland Caribou, Meadow Vole) → surface area to volume ratio – the ratio associated with heat loss; a smaller ratio is much better for retaining body heat. → countercurrent heat exchanger – a system of arteries and veins in such close proximity to each other that heat is transferred between them. (examples – bird feet to stand on ice, beaver/otter tails, nasal passages of animals to warm air) - rete mirabile – (Latin for 'wonderful net') is a complex of arteries and veins lying very close to each other, found in some vertebrates. The rete mirabile utilizes countercurrent blood flow within the net (blood flowing in opposite directions). It exchanges heat, ions, or gases between vessel walls so that the two bloodstreams within the rete maintain a gradient with respect to temperature, or concentration of gases or solutes. (examples – bird feet to stand on ice, beaver/otter tails.) → torpor – a state of dormancy in which the body temperature drops to well below normal, and the animal enters a state of controlled hypothermia. –usually short-term, overnight (example – Black-capped Chickadees, White-footed Mice, Meadow Voles, Hummingbirds, Common Poorwills (enter the longest periods of torpor – on and off for months)) → controlled hypothermia – whereby an endotherm allows its body temperature to drop below its normal operating level, as occurs during torpor; a physiological response to sub-zero temperatures. Behavioural adaptations - Tail around the face, curl in to a ball. - breathing through the nose to increase air temperature as it enters the body – this is another countercurrent heat exchanger - birds tucking extremities under wing can keep it warm. - Roost site selection – coniferous trees offer warmth trunk hallows (examples - Black-capped Chickadees, Owls, Woodpeckers) → huddling – a behavioural adaptation for cold temperatures in which animals crowd together into a ball-like group that collectively shares body heat and creates a better surface area to volume ratio for conserving heat and energy (examples – Meadow Voles, Flying Squirrels, Tree Swallows) - build shelter – snow/mud insulates (muskrat lodges made of cattails, beaver lodges made of mud and sticks). - breathing holes means they’re occupied. - small animals find warmth under the snow – burrowing in the subnivean space (voles, small insects) or burrow in snow to sleep (examples – Ruffed Grouse, Common Redpolls) → subnivean space – the crystalized zone of snow cover next to the ground, and through which small animals move around in winter. (example – Red Squirrels. Shrews.) → basking – thermoregulating by exposing the maximum surface area of an animal’s body to the sun. Ectotherm strategies to combat cold → herpetiles (herps) – collectively reptiles and amphibians - herpetiles find a suitable place to enter dormancy. Below the frost line (American Toad, or Spotted Salamander digs or uses animal burrows), or the bottom of ponds (Bullfrog). Must stay above freezing or they will die - ectotherms cannot truly hibernate because they do not regulate their internal temperature – ectotherms enter dormancy → hibernaculum – the site in which an animal spends winter dormancy used by animals that undergo long periods of dormancy (example – bats and snakes.) – snakes will travel long distances to the same place year after year. - Insects and other invertebrates go dormant above the frost line (example - Woolly Bear caterpillars) → cryoprotectant – a biochemical compound that prevents tissues from freezing; (i.e. glycerol) → glycerol – a sugar alcohol commonly used as a cryoprotectant in dormant animals. - glucose – an alternate cryoprotectant in some animals → supercooling – the lowering of a liquid’s temperature to below its normal freezing point without it freezing - Some insects winter in cocoons (chrysalids – example Swallowtails), some as adults (example – Anglewing Butterfly) some as eggs. → ootheca – the hard foam egg case of certain animals (i.e. Praying Mantids) - Walking Sticks overwinter as eggs that attract ants, which take the egg to their nest and feed part of the egg, the capitula, to their larvae. After the larvae have consumed the capitula, the ants take the egg to their waste disposal area where it hatches when ready. - some insects overwinter in galls. (example - Goldenrod Gall Flies grub) → gall – abnormal tissue growth on a plant; usually induced by an insect or mite that resides inside the gall eating its tissues. → freeze tolerance – a the ability of animals to survive intercellular ice inside the body (example – Goldenrod Gall Flies grub, Grey Tree Frog, Wood Frog, Spring Peeper Frog, Striped Chorus Frog, Hatchling Blandings Turtle, Hatchling Painted Turtle, Garter Snakes) – this freeze tolerance is achieved by cryoprotectants inside the cells, with ice nucleating sites between them. - supercooling is no ice in the body -> freeze tolerance is ice between the cells Inactive endotherm strategies to combat cold - endotherms are not freeze tolerant → lethargy – a light state of dormancy in which an animal is easily roused when the ambient temperature rises, and it’s body temperature does not drop as much as in hibernation. (example – racoons, skunks undergo lethargy in sheltered dens. Chipmunks semi-hibernate but wake up to eat, or crap) - prolonged lethargy is what bears do – not true hibernation because they are easily roused and body temperature stays rather high. They eat a lot and climb trees for acorns and beechnuts and stuff before winter to get fat. Form a tappen so they don’t foul the den → tappen – a rectal plug that forms in dormant bears → hibernation – a long-term dormancy in which heart, respiratory and metabolic rates fall to very low levels and the body temperature drops to below 10C; also called deep or true hibernation. (examples – Groundhog, Meadow Jumping Mice) Mobility Challenges Physical Adaptations - Large Feet – some animals have enlarged feet that act as snowshoes to increase mobility over snow covered areas (Snowshoe Hares, Northern Weasels, Caribou, Northern Ptarmigan. Ruffed Grouse (special scales grow on feet for winter)) Long Legs – some animals have long legs. (Moose) Behavioural Adaptations - browse line - In areas where many deer live, a noticeable “browse line” appears on trees where the deer have repeatedly reached up to eat low-hanging twigs and branches. - wolves walks single file in each other’s footsteps to conserve energy - otters and mink make slides (called tobogganing) Migration → migration – an annual, two-way journey that is primarily a response to a predictable food shortage; often spans thousands of kilometres (examples – birds, Monarch Butterfly, Green Darner dragonfly) Arctic Tern ex-world champion migratory bird. New champion is a sandpiper called Red Knot - songbirds migrate at night. (water conservation, still wind, less predators) → bounding flight – an energy efficient, roller-coaster form of flight adopted by migrating songbirds → thermal hopping – whereby migrating birds (i.e. hawks, eagles, vultures) move by soaring up one thermal and gliding down to the base of the next - birds store fat as energy for the migration journey. Fat is the fuel of choice used by migrators because it does not require additional water to be stored for its metabolism. → hyperphagia – an increased appetite leading to the excessive consumption of food; experienced by birds prior to migration. → hyperlipogenesis – the accelerated synthesis of fat to create large stores of energy in birds preparing for migration (examples – Semipalmated Sandpipers double their body weight in 10 days) - hummingbirds migrate during the day because they need to feed along the way due to energy consumption - blackbirds migrate in big flocks - daytime migrants navigate by the sun, landforms and other visual cues. - nocturnal migrants use visual cues by constellation patterns. - both day and night migrants use the earth’s magnetic field. → rhodopsin – a photopigment in the retina of birds that is believed to play a role in detecting the earth’s magnetic field during migration. → photopigment – a pigment that reacts to sunlight. - geese form V because the turbulence from the bird in front adds lift. Plant cold weather strategies - roots stay under ground in a dormant state → cold hardiness – in plants, the ability to survive sub-zero temperatures without tissue damage; the equivalent of freeze tolerance in animals. - acclimation – how plants become cold hardy, in two stages - acclimation is triggered by a change in the photoperiod - second stage is triggered by cold temperatures → photoperiod – the period of time during which an organism is exposed to light each day. → phytochrome – a photopigment in plants. - decrease water content in cells, increase sugars, anti-freeze protein. different cell walls all increase cold hardiness. - xanthophyll pigments protect conifer needles from desiccation during the winter due to increased solar radiation. - conifer reduce water loss with small surface area, closing stomata, thick cuticles - skunk Cabbage produces its own heat. - ferns curl up to reduce surface area during the winter. - deciduous trees drop leaves before winter. Weight of snow on plants - deciduous trees drop leaves - coniferous trees are spire shaped (example - Balsam Fir) or spindly (example - Black Spruce) to drop snow, small needles for leaves, shorter branches Hot weather strategies → abscisic acid – a hormone that plays important roles in plant biology (i.e. reducing metabolic activity); often released in times of abiotic stress. → aestivation – a state of reduced metabolic activity (a type of dormancy) that is an adaptive response to high temperatures. → obelisk – a thermoregulatory posture adopted by dragonflies in response to extreme heat involves raising the abdomen so as to shade the thorax and head, and reduce the body’s surface area in direct contact with sunlight → stilting – a heat-avoidance posture of Tiger Beatles in which the body is elevated above the sand by the fully extended legs - animals pump more blood to the extremities in hot weather to try lose heat - Honeybees work together to cool the hive and use their wings to create a fan-like airflow. → evaporative cooling – the removal of excess body heat through the evaporation of water (example – sweating, panting. Birds also pant) → gular fluttering – the rapid vibration of throat muscles to increase airflow and evaporative cooling in the respiratory tract of large birds (i.e. owls, cormorants, boobies) - vultures pee on their legs to cool off. - Mourning Doves enter hyperthermia A Resourceful Menu (Chapter 3) - animals consume, and plants manufactures Animal food solutions Animals that Eat Plants (Herbivory) → herbivore – an animal whose primary food is the tissues of plants. - every part of the plant (leaves, seeds, nectar, sap, bark and twigs, etc) are consumed • herbivore examples – Maple Spindle Gall mites, eat the leaves from the inside out. Animals that on decomposing organic materials → detritivore – an animal whose primary food is detritus. → detritus – particulate debris formed by decomposing organic materials (i.e., dead leaves, moulted feathers, pine pollen) • detritivore examples – Millipede, Earth Worms (0 species are native to Ontario) Animals that feed in moving water → filter feeding – extracting nutrients by filtering them from a medium, usually water. → labral brush – the modified umbrella-like mouthparts used for filter-feeding by larval Black Flies. → lamellae – comb-like structures on the sides of duck bills that act as sieves to separate edible particles from water when a dark is filter feeding. - filter feeding examples – larval Black Flies, attach themselves to a rock with silk, float around, use labral brush to continuously scoop food to mouth. Puddle Ducks (also called Dabblers) or Mallard using the lamellae and fuzzy tongue. Some Swans and Geese also filter-feed. Freshwater Sponge is a stinky and crunchy colony of filter feeders. All plant foods require feeding adaptions Nectar → proboscis – the elongated mouthparts of an insect, often used to suck liquids. (Examples – butterflies, moths. They coil the proboscis up when it’s not needed – these are siphoning insects) → hyoid apparatus (hyoid horns, hyoid process) – a structure made of cartilage and bone, situated at the base of a woodpecker or hummingbird’s tongue, that is moved by muscles and ligaments, causing the tongue to extend well beyond the tip of the beak. Sap - stylet – used to reach sap in phloem tissues (Examples - Treehopper, Leafhopper, Spittle Bug, Aphids – these are piercing and sucking insects) Tissues - source of carbohydrates for animals (Examples - Groundhog, Moose) - as covered in the plant defences chapter: plants have protective structures, thorns, prickles and also cellulose, hemicellulose, pectin and other structural components are digestibility reducers. Ingesting adaptations → radula – the rasping tool in the mouth of a gastropod that rips off pieces of plant material; analogous to mammalian incisors. (Examples – slugs and snails, like a chainsaw) - modified mandibles – external mouthparts used to cut plant tissues (examples – Caterpillars – chewing insects.) - leaf miners – some caterpillars eat a leaf from the inside. (Example Leaf Blotch Miner) - incisers – used by mammals (examples - Beaver chew wood with incisors that never stop growing and self-sharpen. The tooth enamel on the front is orange because of iron, the back is dentine. Moose and Deer have only bottom incisors, they jab and rip foliage off. Ribbed cheek teeth grind food like a cheese grater) → masseters – muscles that power a mammal’s cheek teeth for the mastication of food. (these muscles power the back teeth) → temporalis muscle – the jaw muscles that power the bite; well developed in carnivores. → cheek teeth – collectively the molars and premolars. → gizzard – the muscular digestive organ of a bird that grinds up hard objects (i.e., seeds); especially well developed in granivorous and seed-eating birds. Grit (stones are consumed to stay in the gizzard) → analogous structure – the part of an organism serving the same function as a different part of another organism; i.e., the cheek teeth of mammals, insect radula or mandibles and the gizzard of birds are analogous structures → granivore – an animal whose primary food is the seeds of plants - animals can eat other parts of plants. Buds (Ruffed Grouse), Conifer needles (Spruce grouse) Digestion adaptations - break down of the material internally with digestive enzymes - slugs and snails produce digestive enzymes - caterpillars eat a lot but waste a lot due to low digestive enzymes → frass – the fancy name for insect faeces. → rumen – the first of four stomach compartments possessed by ruminants; contains bacteria and other microbe symbionts (like bacteria) that break down cellulose and other structural components → ruminants – a herbivore that has a rumen and regurgitates a cud. (Examples – Moose) → cud – a lump of partly digested plant material that has been regurgitated from the rumen for further mastication and digestion; done by ruminants. → caecum (caeca, plural) – a pouch or sac-like extension at the junction of the intestines in herbivores; contains bacteria and other microbes that assist in digestion. (Examples – Hares, Rabbits, Beavers, Grouse) → coprophagy – the consumption of excrement. (beavers and rabbits process their food twice by eating their own droppings) - large digestive tracts, 26% total weight, of porcupines (they do not eat their droppings) Fruit - a major source of food for birds - Black Bears eat blueberries - fruit eating birds prefer pulp or flesh of fruit and they help the plant by dispersing seeds - Waxwings are as close as they come - Fruit is lacking in some nutrients that animals need for a complete diet. To combat this they need to eat a large volume of fruit. As an adaptation most fruit eating animals have adaptations like large gapes, small gizzards and short intestines. (So they can eat and pass berries quickly through the system – 20 minutes in some cases) (fruit eating examples – Waxwings) Seeds or Nuts - eating fruit and eating seeds is not the same thing - seed predators - crack the seeds open before consumption. This is not good for the plant - examples of seed predators, various Finches. Grosbeaks has a massive conical bills for crushing and slicing like a can opener. American Goldfinches, eat seeds from thistle with their small, fine bills. Red Crossbills have odd crossed over bills eat pine, spruce and other conifer cones. - non-finch seed predator examples – Chickadees and Bluebirds hammer seeds open with their bills. → niche partitioning – the division of resources that allows different species of animals to share a habitat while avoiding excessive competition. - grit in the gizzard aids in the breakdown of seeds. Animal adaptations to deal with plant chemical defenses - some herbivores sequester chemical defences for their own uses (example MIlkweed Caterpillars, Monarch Butterfly, Milkweed Beatle they cut the veins of the plants to stop the flow of chemical defenses (also called vein drain) → mixed function oxidases (MFO) – a complex of enzymes used by herbivores to neutralize toxins (i.e. terpenoids and alkaloids) in plants (Example – Beaver) Diet Categories - specialists, eating only one or two kinds of food (Examples - Red-headed Pine Sawflies eat pine needles. Monarch Caterpillars eat only milkweed leaves and buds - generalists are animals that eat diverse plants (Example – Beaver eats bark, leaves, roots) - seasonally switches food for a balanced diet (Example – moose eat fresh leaves and twigs with high carbohydrates protein, low sodium about 20 kg a day. In winter they eat Balsam Fir very low sodium, low moisture. In summer they eat Aquatic plants with high sodium to store sodium in the rumen. In early spring moose drink mud in ditches to get road salt (sodium chloride) Animals Eating Animals - advantages of eating animals - high protein - easier to digest - disadvantage of eating animals - hard to catch - hard to find - animal fights back Adaptations developed to help animals eat other animals - predation – a biological interaction where a predator (an animal that is hunting) feeds on its prey (the animal that is attacked). Predators may or may not kill their prey prior to feeding on them, but the act of predation often results in the death of its prey and the eventual absorption of the prey’s tissue through consumption → parasitoid – an animal that lives in or on, and obtains its nutrition directly from, another living animal (called the host), killing it in the process; usually smaller, sometimes only marginally, than the host → parasite – an animal that lives in or on, and obtains its nutrition directly from another and usually much larger living animal (see host), usually without killing it. → scavenger – an animal that obtains all or part of its nutrition by eating dead animals. Predation Predator challenges - locate - capture - immobilize Locate Visual Adaptations - Haws, keen eyesight, large number of cones and depth perception. - fovea – a part of the eye, located in the center of the retina; responsible for sharp central vision, which is necessary when visual detail is of primary importance. - Owls, large eyes with special glycogen rich rods to capture more light at night. Eyes have frontal placement for depth perception. Due to decreased field of view owls turn their head 270 degrees. Also have a way to magnify vision up to 2-3 times. - Tiger Beetles – have large compound eyes, Ground Beetles hunt at night. Dragonflies have compound eyes, Whirligig, Jumping Spiders have 8 simple eyes and can scan prey with the main pair of eyes by moving the retina. Crab Spiders are visual hunters. → ommatidium (ommatidia, plural) – a single unit of an insect’s compound eye. Hearing adaptations - Large ears (Examples – fox, eastern wolf) - owls hear very well with no external pinnae; offset asymmetrical ears openings and wide heads to allow pinpointing of sound. → facial discs – concentric rings of feathers on an owl’s face that help to capture and direct sound to the ear openings; harriers also possess facial discs. → echolocation – the use of ultrasound for locating prey used by many bats and some shrews Smell (olfactory) adaptations - Elongated snouts - vomeronasal organ is also used by predators → flehmen – a characteristic pose of larger mammals when picking up airborne pheromones; the head is raise, mouth opened, and lips pulled back to better expose the Jacobson organ - predators hunt at sunset because the air is cooler; the colder air on top holds better smell Tactile adaptations → tactile – of or pertaining to the sense of touch • tactile examples – Raccoons have touch sensitive paws, River Otters have tactile sensors called vibrissae hair around the mouth to locate prey when it is hard to see → vibrissae – large hair or whiskers that serve a mechanosensory function, often near the mouths of carnivores. • Vibrissae examples – Fox, River Otters → mechanosensory – of or pertaining to tactile sensory reception. → mechanoreceptor cell – a sensory cell that responds to tactile stimulation. → rictal bristles – hair-like feathers around the mouth (rictus) of some birds (i.e. flycatchers and raptors); easier to clean, and may have protective or sensory functions • rictal bristles examples – Eastern Whip-Poor-Will → Eimer’s Organ – tactile bulbous outgrowths of the epidermis; the twenty-two protuberances on a Starnosed Mole’s nose collectively contain 25,000 Eimer’s organs. → herbst corpuscles – a pressure-sensitive group of cells associated with tactile sensory perception; also called Corpuscles of Herbst. • Examples herbst corpuscles – sandpipers (such as American Woodcock a
More Less

Related notes for BIOL 1902

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.