Today: Today: A Few More PresentationsA Few More PresentationsMore More Plants!Plants!Animals!Animals!

What will life on land be like?!?

Thinking Thinking About the About the Plants…Plants…

What will life on land be like?!?

The BryophytesThe Bryophytes Mosses, liverworts and hornwortsMosses, liverworts and hornworts Nonvascular plant (short!)Nonvascular plant (short!) Dependent on moist habitatDependent on moist habitat

Life Cycle of Life Cycle of a Typical a Typical

Moss Moss (Bryophyte)(Bryophyte)

Drought-Tolerant MossesDrought-Tolerant MossesMany species of moss can survive drastic Many species of moss can survive drastic

plasmolysis. Rehydrated plants repair plasmolysis. Rehydrated plants repair most internal damage within minutes most internal damage within minutes (drought repair genes!). Respiration (drought repair genes!). Respiration resumes in minutes; photosynthesis resumes in minutes; photosynthesis

resumes within 24 hours!resumes within 24 hours!

Scientists at the USDA are eager to learn more about these

drought resistant genes!

Seedless Vascular Plants:Seedless Vascular Plants:

Whisk ferns, Whisk ferns, lycophytes, lycophytes, horsetails and fernshorsetails and ferns

Much larger (true Much larger (true vascular tissues!)vascular tissues!)

Still dependent on Still dependent on water for water for reproductionreproduction

A Typical Fern LifecycleA Typical Fern Lifecycle

Which generation is “dominant”? How does this compare to the mosses??

The Beginning of a Trend?The Beginning of a Trend?

The GymnospermsThe Gymnosperms“Naked Seeds”“Naked Seeds”

3 Major Adaptations:3 Major Adaptations:

1.1. Continued Continued reduction of reduction of gametophytegametophyte

2.2. Evolution of the Evolution of the seedseed

3.3. Evolution of Evolution of pollenpollen

Arabidopsis thaliana pollen grains Microscopy by Juergen

Berger, computer image manipulation by Heiko Schoof

GymnospermsGymnospermsOvules and seed develop on the surface Ovules and seed develop on the surface

of specialized leaves called scalesof specialized leaves called scales

OVULEOVULE

After After fertilization, fertilization,

the ovule the ovule develops into develops into

a a SEEDSEED..

The SeedThe Seed

Into the Angiosperms!Into the Angiosperms!

Angiosperms: The Flowering Angiosperms: The Flowering PlantsPlants

Fruits are Mature Ovaries!Fruits are Mature Ovaries!Fruits protect seeds and aid in their Fruits protect seeds and aid in their

dispersal.dispersal.

Ovary wall becomes the thickened wall of Ovary wall becomes the thickened wall of the fruit.the fruit.

Quick Scavenger Hunt!Quick Scavenger Hunt!(In-Class, Part 1)(In-Class, Part 1)

With your group, With your group, find one find one example of each example of each of the four major of the four major groups!groups!

The Animal Kingdom- General The Animal Kingdom- General Characteristics:Characteristics:

Multicellular Multicellular Heterotrophic (via ingestion) Heterotrophic (via ingestion) EukaryotesEukaryotes Require Oxygen for aerobic respirationRequire Oxygen for aerobic respiration Reproduce sexually (and possibly Reproduce sexually (and possibly

asexually)asexually) Motile during part of the life cycleMotile during part of the life cycle Life cycle includes stages of developmentLife cycle includes stages of development

You Try: Questions 2 & 3

Animal Body PlansAnimal Body PlansMostly Mostly INVERTEBRATESINVERTEBRATES (no backbone) (no backbone)

vs.vs.

VERTEBRATES VERTEBRATES (with backbone)(with backbone)

Animal Body Plans: Animal Body Plans: SymmetrySymmetry

The The GUTGUT = a tube or sac projecting into the = a tube or sac projecting into the body where food is digested and absorbedbody where food is digested and absorbed

Guts can be Guts can be saclikesaclike with a single opening, with a single opening, or or tubulartubular with openings at two ends with openings at two ends

Animal Body Plans: The Animal Body Plans: The GutGut

Many animals have Many animals have a cavity between a cavity between the gut and the the gut and the body wall called body wall called

a a COELOM.COELOM.

Animal Body Plans: Body Animal Body Plans: Body CavitiesCavities

Coeloms allow animals to be larger Coeloms allow animals to be larger and more complex by cushioning and more complex by cushioning and protecting internal organs.and protecting internal organs.

An Evolutionary Overview of the

Animals

The SpongesThe Sponges

Lined with collar Lined with collar cells- create cells- create currents, trap foodcurrents, trap food

Skeleton composed Skeleton composed of spiculesof spicules

Ancestral lineage- no Ancestral lineage- no true true tissuestissuesNo SymmetryNo Symmetry

The SpongesThe Sponges

An Evolutionary Overview of the

Animals

The CnidariansThe Cnidarians Radially symmetricalRadially symmetrical Tentacled animalsTentacled animals Mostly marineMostly marine Have true tissuesHave true tissues Make cnidocytes (stinging cells)Make cnidocytes (stinging cells)

The CnidariansThe Cnidarians

The FlatwormsThe Flatworms Bilateral Bilateral

SymmetrySymmetry Earliest extensive Earliest extensive

organ-system organ-system developmentdevelopment

Nervous system Nervous system with small “brain”with small “brain”

Cephalization Cephalization evident evident (eyespots!)(eyespots!)

Digestive track Digestive track has single has single openingopening

The Diversity of FlatwormsThe Diversity of FlatwormsThe Flukes:

Planaria:

Tapeworms:

TapewormsTapeworms

The RoundwormsThe Roundworms Digestive tract Digestive tract

completecomplete Very Abundant! Very Abundant!

Ascaris:

Trichinella:

Vinegar Eels:

The Annelids (Segmented Worms)The Annelids (Segmented Worms) Also True Coelomates Also True Coelomates Most use bristles on each side of body for Most use bristles on each side of body for

locomotionlocomotion Nervous system, one-way gutNervous system, one-way gut Primarily free-livingPrimarily free-living

Leeches:

Earthworm

(Lumbricus):

The ArthropodsThe Arthropods Segmented body, covered by Segmented body, covered by

exoskeletonexoskeleton Typically divided into 3 sections: the head, Typically divided into 3 sections: the head,

thorax, and abdomenthorax, and abdomen More than 1 million identified species!More than 1 million identified species! Well-developed nervous systemWell-developed nervous system

Three major existing groups of Arthropods:Three major existing groups of Arthropods:

1.1. Chelicerates (spiders)Chelicerates (spiders)

2.2. Crustaceans (crabs and shrimp)Crustaceans (crabs and shrimp)

3.3. InsectsInsects

Arthropod DiversityArthropod Diversity

The MolluscsThe Molluscs Bilaterally symmetrical, true coelomBilaterally symmetrical, true coelom General body plan includes the head-foot, the General body plan includes the head-foot, the

visceral mass, and mantle (secretes shell)visceral mass, and mantle (secretes shell)

The Molluscs: DiversityThe Molluscs: Diversity

Gastropods (“belly foots”)

The Chitons

Bivalves

The Cephalopods

The EchinodermataThe Echinodermata 5-part body plan5-part body plan Water vascular system w/tube Water vascular system w/tube

feetfeet Bilateral larvae w/ “radial” Bilateral larvae w/ “radial”

adultsadults Spiny skin, internal skeletonSpiny skin, internal skeleton

The ChordatesThe Chordates4 Common Features:4 Common Features:

1. Flexible supporting skeletal 1. Flexible supporting skeletal rod called a rod called a notochordnotochord

2. 2. Dorsal hollow nerve cordDorsal hollow nerve cord above the notochordabove the notochord

3. 3. Gill slitsGill slits in the pharynx in the pharynx

4. 4. Post anal tailPost anal tail

The Invertebrate Chordates- The Invertebrate Chordates- Tunicates!Tunicates!

•No backbone

•Larval form has all four traits; sessile adult looks nothing like a chordate!

A bony spinal or vertebral column A bony spinal or vertebral column replaces the notochord, and replaces the notochord, and encases the dorsal nerve cordencases the dorsal nerve cord

Skull surrounds the brainSkull surrounds the brain Can be divided into Aquatic, Can be divided into Aquatic,

Transitional, and Terrestrial Transitional, and Terrestrial VertebratesVertebrates

The Chordates: The The Chordates: The VertebratesVertebrates

The Aquatic VertebratesThe Aquatic Vertebrates Oldest= Jawless fishOldest= Jawless fish May have cartilaginous or bony skeletonMay have cartilaginous or bony skeleton

The Transitional Vertebrates The Transitional Vertebrates (Amphibians)(Amphibians)

Incompletely adapted to terrestrial Incompletely adapted to terrestrial environmentsenvironments

Dependent on water for reproductionDependent on water for reproduction

Terrestrial VertebratesTerrestrial VertebratesReptiles, Birds and MammalsReptiles, Birds and Mammals

Key Reptilian Evolutionary Key Reptilian Evolutionary InnovationsInnovations

Tough, scaly skin to reduce water lossTough, scaly skin to reduce water loss Internal fertilizationInternal fertilization Efficient kidneysEfficient kidneys Amniote eggs protect youngAmniote eggs protect young

The Chordates: Evolutionary The Chordates: Evolutionary LineagesLineages

MammalsMammals Hair and Mammary GlandsHair and Mammary Glands Behavioral FlexibilityBehavioral Flexibility Modified TeethModified Teeth Endotherms (high metabolic Endotherms (high metabolic

rates)rates)

Mammalian LineagesMammalian Lineages1.1. Egg-laying mammals (monotremes)Egg-laying mammals (monotremes)

2.2. Pouched Mammals (Marsupials)Pouched Mammals (Marsupials)

3.3. Placental Mammals (eutherians)Placental Mammals (eutherians)

Spiny anteater- an egg-laying

mammal

Koalas- Marsupials Humans- Placental MammalsYou Try: Question 4