urban landscape 1 Flashcards
Urban Landscape
- Urban areas are full of life byt typified by distubrbance
○ Disturbance is an event in time that disurpts the ecosystem, community or population structure and changes resoruces, susyrate availbility or physical envrinment- Human propogated plant monocultures are disurpted by adventitious or resilient pioneer species
○ Pioneer species are thriving in barren or recently distrubed spaces - Pollution, human contact, phsycoal barriers like pavment all make up unique challenges of urban living
- Some animals have thrived in the urban landscape even tho they are found in other places
We now look at how these animals eveolved to adapt to these envrinments even tho they have to deal with all types of pollution, temps etc
- Human propogated plant monocultures are disurpted by adventitious or resilient pioneer species
The city as an island
- Cities have largely replaced vegetation
- Concrete and asphalt readily absorb heat and radiate warmth long after the sun has gone down
○ Combustion, indoor heating radiation also creates heat within large cities - Cities are often 10-15 degrees warmer than rural surroundings
- Urban heat islands create unique settings for the organisms within
- Air pollution promotes signifcantly more rain within cities
○ Bc the degree of paved ground, signifant run off occurs from cities requring extensive rain water drainage systems and ponds - In rural areas theres greater cooling from evaporation and plant transpiration whichc ant be found in the cities
Water cnt be absorbed into the earth by concenrte unlike vegeation areas
- Concrete and asphalt readily absorb heat and radiate warmth long after the sun has gone down
Urban landscape habitats and resposnes
- Animals and plants in the urban landscape encounter diverse microhabitats
- These may be natural or human made
- These landscapes both take in additional nutrients, and lose greater amounts of nutrients than surrounding rural areas
- The four broad categories of the habitats are:
○ Built habitats are structured primarly by human constructin
○ Waste habitats have been largely replaced with human discards
○ Green habiatts are covered by plants mostly
○ Aquatic habitats are covered mostly by water - Some organisms persist by adpating to these extreem conditions, a few organisms exploit them and become widespread and many organisms cannot tolerate them and must avoid cities
- Three responses toc challenges or urban life:
○ Avoid cities
§ Like wolves
○ Adapt to the density:
§ Racoons, red fox
○ Exploit:
§ Thrive in the city and some can be non native and they get to a high density and benefit by being close to humans
Pigeon rat
Organisms of the landscape
- Desirable plants- trees, grass, ornamental flowers
- Less desribale - “weeds”
- Lichens
- Worms
- Insects
○ Flies/maggots
○ Mosquitos
○ Ants
○ Cockroachs
○ Bed bugs - Spiders and ticks
- Mammals
- Birds
Desirable and undesirbale
- Desirable plants - trees, grass, ornamental flowers
- Less desirbale weeds
○ Plants cannt move and must grow from seed
○ Succesful species must grow quickly from seed, tolerate high nutrient levels and toxic contaminents
○ The most succesful rely on wind or human distribution for their seeds
○ Many are angiosperms - seed plants that bear fruits - bc we plant tehse including grass
Some species like elss derisble ones can be rlly succesful bc huamns and animals carry them and then they thrive as pioneer species
- Less desirbale weeds
Lichens
○ A polyphyletic group
○ Lichens are composite organisms, symbiosies of fungi and yeast (mycobionts) and cyanobacteria or green algae (phycobionts); they clearly do not fit into standard monophyletic classfication schemes
○ They grow in symbosiis with those photosynethci organisms and they harvest nutreints from the photosyntehsis
○ Lichen is a good thing to see bc it means tehre isnt much pollution
○ There is crustose, foliose (leaf like) and fruticose (with stalks)
○ Not monophyletic groupings bc the fungi and algae cells they don’t live independtly it’s a symbiotic asscoiation
○ Lichens are found anywhere - they breka down and wether rocks
○ Lichens are ubiqitous and often grow in extreme habitats (bare rocks artic and alpine slopes); some photosyntehsize at -18 degrees and survive -198 degrees; lichens survive extreem water stress
○ Lichens are sensitve to pollution in cities and acid rain
○ Lichens are slow growing
These organism are indctaors in the urban landscape of good air quality
Worms
○ Phylum annelida
○ Segmented round worms
○ Bilateral symmetry
○ Many diverse annelids live in ocean
○ On land there are few major types but includes earthworms
○ Earthworms belong to class clitellata
§ All share clitellum, involved in reproduction
§ Include earthwroms and relatives the leches
§ Most found in freshwater or terrestrial (moist)
§ Marine and parasitic forms as well
○ Why do worms come up in the rain?
§ Worms are sensitive to aniamls, moving to the surface purposefully - they can feel the vibrations of u coming near and come back into their burrow
§ Movement:
□ The sgemented body allows complex movements along the body
□ They can contract circular msucles and the segmented become elongated and skinny
□ They can contract the longitudinal muscles and the segments become short and wide which helps anchor the body
□ Metamerism allos great complexity - indepent movement of each segmeent, needs more complex nervous system and if one segement is injured the animal can still function - metamerism also occurs in arthorpods
□ The segements are called metameres or somites
□ They move by alnternatiing which part is contracting
□ Setae are found in annelids and aid in moevemnt - they extend from pores in cuticle - act as anchors in earthworms - moved by msucles - 4 pairs per sgement - helps to anchro body and facilitate moveemnt
§ Feeding:
□ They are scavenegers, eating mostly decaying organisms
□ Mouth at anterior end
□ Soil consumed as they move
□ Large amounts fo waste produced - complete gut
□ Contirbute to mixng and aerating soil
□ Food for birds, amphibains and many mammals
§ Respiration:
□ No specialized organs for respiration
□ Moist skin allows passive trasnfer of gases across body covering to blood
□ Hemoglobin in blood carries oxygen, carbon diozide released
□ Circulatory system is present to allow gas exchange throughout the body
□ They like it to be moist so rain doesn’t matteyr
§ Mating and reproduction:
□ They leave their burrow for this
□ Earthworm reproduction is sexual
□ Direct development - no metamorphosis
□ Juveniles resemble adults but smaller
□ Clitellum - ring of secretory cells - derived character shared by clitellates - secretes mucous to join pair
□ Earthworms are hemaprodites an both membrers of the pair swap gametes
□ Eggs are laid into soil, mucus forms a coccoon
§ The reason why they are onc ocneret is to mate but also bc on conceret they lose the ability to tell hwere they are - they become disorientated
§ What earthworm do in nature?
□ Intestines of the soil
□ Imprtant in the breakdown of organic matter, mixing of soils
□ Sign of healthy soils
Important as food sourve for birds, snakes, mammals, invertebrates etc
Arthropods
ontains 5 distinct subphyla
§ Crustacea and hexapoda form the clade pancrustacea
§ Myriapoda: centipedes
§ Chelicerata: spiders
§ Trilobita: extinct
§ Crustacea: lobster
§ Hexapoda: insects
○ Arthrpod exoskeleton:
§ Thin epictucile - waxy testure no chitin
§ Multiple layers of procuticle:
□ Made of chitin bound with protein
□ Lightweight and felxible
□ Proetcts against dehydration
§ Before molting the exocuticle is produced
□ Exocutivle is waxy and prevents those who leave humid areas from drying out
§ Epidermis - secretes cuticle
§ At the jointed areas, the cuticle is very thin to allow movement
Over the entire body, exoskelton is mde up of plates joined by flexible hinges
Class insecta
part of subphyla hexapods (doesnt include spiders or ticks)
§ Body made up of three sections: head thorax and abdomen
§ Most have two pairs of wings on thorax
§ Includes bees, beeetles, grasshoppers etc. - not spiders
§ There are more species of insects than all other animals combines
§ Play integral roles in the envrinment, imprtant medical and econimic roles in human life
§ They are found everywhere but open ocean
§ Abudant in frshwater, soil, forests and even deserts and wastelands
§ Larval and nymph stages can be common in water
§ One key to wide dirtbution was mobility and flight
§ Flight:
□ Insect wings are outgrowths of cuticle from the thorax
□ Not homologpus to bird or flying mammal wings
□ Most insects have two pairs of wings (true flies have 1)
□ Wings can be used for flight (thin and delicate) or modified for protection (thick and horned)
§ Feeding:
□ Most insects feed on plant fluids or tissues (herbivourous)
□ Many beetles and sinsect larvae feed on dead animals
□ Some insects catch live prey (predaceous)
□ Many insects are parasitic at some point in their life cycle
□ Many wasps are parasites that always kills their host; a parasitoid
□ Others are general pests that tarsnmit diseases, dmaage strcutrues, destory argiculture
□ Their mouth parts are variable and show adaption to life cycle
§ Nervous System and Sense organs:
□ Many nevrous sense organs make insect exceptionally snesitve to thir nevirnments
□ Most obivosu are antennae used for sensing tocuh, taste, sound
□ Toch, pressure, vibration etc
® Single hair like satae
® May use more complex organs
® Common on antennae, legs body
□ Hearing
® Senstive sate detct airborne sounds
® Organs on legs detect vibrtaions on surface/susbstrate
□ Taste and smell
® Bundles of snesory cells in sensory pits
® These are located on mouthparts, antennae, legs
® Important for feeding, mating, host parasite relationships
□ Sight
® Two types of insect eyes: simple and componud
® Simpel eyes have single lens - for detecting light
® Compound eyes have many lenses - stitch togetehr image
◊ Single unit if ommatildia
◊ Each works like separate tiny eye containg pigemnts
◊ Eye sees in all direction simulatnesly but image is fuzzy
◊ Cornaea, trsparnet cuticle covers eye
□ Reproduction:
® Sexual reprodyction is norm
® Sexes are separate
® Attarcting mates is imprtant and can ivolve smelly pheremones, flashy bioluminscence, loud calls or seductive corutship moveemnts
® Fertlziation occurs internally
® Females may mate only ocnce and store sperm to fertlzie eggs for remainder of their lives or may mate with multipel males
® Metamorphasis allows dveeloping insects to grow in size or use new resources
◊ Envrinemtal cues causes chnages to production of hormones that control molting
® Jeavaniles are adapted to sit and not be movile until they get wings
□ Reproduction Diapause:
® Annual dormancy period
® Part of life cycle
® Winter - hibernation
® Summer -estivation
® Any life stage may stay dormant to survive adverse conditions
® Trigegred by envrimental cues (day lengths etc.)
® Always occurs at end of active growth stage
Isnect is then redy for next molt
Class insecta diveristy
§ Insect orders are key for recognzable leevls of diversity
§ Relatevly straightforard to classify insects to at leas their order
Order cleoptera
§ Beetles
□ Forewings are tough, armoured elytra (hardhsell)
□ Larvae may live on land or are aquatic
□ Beetles are most speciocse and diverse type of animals
□ Large chewing mouthparts for general feeding and hervivory and predation
□ Fed upon by many other animals
□ Some psecies are flower pollinators
□ Some are pests of crops plants and trees
Order leopidoptera
§ Butterlfys and moths
§ Wings in scales
§ Mouthparts are tubes to drinking and sucking nectar
§ Caterpilars (larvae) with chewng mouthparts, silk glands for making cocoon
Imprtant pollinators and food for insectivores
Order hymenoprta
§ Ants, bees, wasps
§ Pair of narrow wings may be small
§ Mouthparts (mandibles) for chewing or lapping liquids
§ Ovipoitor sometims specilzied as stinger
§ Larvae are mostly leggless, blind, maggot lik
Often live in eusocial community (queen and sisters or male reproducers)
§ Bees are rpesent as pollinators
§ Wasps are predators and can help maintain biodiversity of other species
§ Ants are high in the urban landscape - natural native organism that have thrived and have rpfound impacts
§ Ants have diverse ecological roles:
□ Seed dispersal - pick and move them into colonies, burrows, cracks etc - moev like heracious plant seeds etc
□ Soil services - stability, aeroation, movement of nutrients - all can haopen underneath stones or pavement
□ Scavenging - 30-60% of food waste is removed by ants by their scavenging - ants are also a competitor for this food when it comes to cockroaches
Pest control - many ants will feed on the pest insects - they can outcompete them and predate on other pest insects
complete metamorphsisi
○ Many of the most common insects have this type of life cycle called the holometabolism or complete metamorphiss
§ Goes from egg, to larval stage, to pupa, to adult
§ The larval stage doesn’t have legs or a head - its much diff than the adult stage
Ants are like this, flies are like this, moths and butterlfies are like this
Order Diptera
§ True flies; house flies; fruit flies; mosquitos etc
§ Single pair of wings
§ Sucking mouthpart
§ Legless larvae - maggots
§ Eggs can be laid in water, human waste, feces etc. (mosquitos do in water)
Prey for many insectovore birds, bats etc, - they are improtant for the food web