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Introduction: Natural Bridges Setting and Tidepool 1. Physical setting microcosm of “- zone” – influenced by 1) river, 2) waves/, 3) wind (NW) Rock Types (wave cut bench) Santa Cruz “Mudstone” hardest rock types resist erosion best- often remain behind forming “” of rock.

–beautiful pocket …. But soft enough to provide complex habitats. 2. Introduction to the inter- tidal AGAIN: this is a STATE PARK PRESERVE- TAKE NOTHING!! Basic concept for pool component: 1. Adaptation.

constantly shaped by pressures of natural selection or .

Physical Environment Shapes Biology – The fundamental resources, and pressures to which a biological system responds by adaptation “ You cannot understand organisms without understanding their physical environment.” Goals

1. Physical Environmental factors: To understand how specific aspects of a marine environments will determine how life adapts-

2. Describe Main Inter-tidal Environments: definitions of main “zones” in intertidal, and to understand each in terms of main physical factors. Issues:

1. - what factors control production ? (base of ?)

2. ALL Organisms- what factors will all organisms have to adapt to deal with? Terrestrial Physical Environments Some Terrestrial Physical variables

* Availability * * Food Availability (Primary production) * Physical Character of Environment *“Stability” of environment Littoral Physical Settings Littoral or Coastal regions:

Temperature: ~varied Food: high Stability: Low! (“High Energy /Low stability”) Phys. Character: Varied, many habitats..

Predict: many many types of life, adapted in many ways.

One common factor? Must Adapt to constant changes. Inter-tidal Special factors:

** WATER availability – how much time do you have to spend dry?

Other Related factors: • Temperature? Major factor • -

• what other big one..? Inter-tidal factors:

**”Stability”?

Very very “Low”

Special adaptations: Must have way to “hold on” and endure huge energy of breaking waves – Can Consider tide zones as function of “time” out of water.. – ALSO = TIME exposed to pounding waves.. A – (what else?)

B Distance

Vertical Inter-tidal Organisms: ZONES based on physical environment= Adaptations “Spray Zone” (above highest tides)

“High tide Zone”

“Mid-tide Zone”

“Low tide Zone”

“Sub-tidal Zone” Below lowest lows “Spray Zone” (above Shallow: Most highest tides) energy, most change “High tide Zone”

“Mid-tide Zone”

Deep: Least “Low tide Zone” energy, Least change “Sub-tidal Zone” Below lowest lows Shallow: Least “Spray Zone” (above % time under highest tides) water – “High tide Zone”

“Mid-tide Zone”

Deep: water “Low tide Zone” 100% of time

“Sub-tidal Zone” Below lowest lows Some Adaptations:

“Spray Zone” (above highest tides)

“High tide Zone”

*Thick shells *systems to prevent drying out “Mid-tide Zone” *resistant to high temp/salinity

“Low tide Zone”

“Sub-tidal Zone” Below lowest lows Natural Bridges Tidepools: example of “Rocky ” • Most organisms live on the surface (epifauna) • Upper zones have mostly shelled organisms • Lower zones have many soft-bodied organisms and Zonation at Natural Bridges High zone

Mid zone

Low zone SPLASH zone pools Baxter points out classic zonation 2. Main Groups Primary Producers-

Q: Based on the physical environment, what would you predict they would be like? 1st: Benthic Primary Producers : - Groups defined by “pigments” they have (recall the “antenna” used to catch light for )

3 groups: Red, Green, Brown

All have some way to “hold” to bottom * specialized cells or structures, often called “holdfasts” (NOT roots!) - “Chlorophyta” “pigments” closest to land plants ie “antenna” = chlorophyls, as on land- live in shallowest water Green Algae- “Chlorophyta”

Some are among most “primitive” Algae

Sea Lettuce: 2 cells “Dead mans fingers”: ~ like a thick…No structures colony- a continuous chain of individual identical cells Red Algae- “Rhodophyta” Pigments most different from land plants ie “antenna” = modified chlorophyl-like molecules, adapted for low and filtered light levels = can extend into deepest water Red Algae- “Rhodophyta”

Many Species secrete calcium carbonate coverings  “Coralline” red algae. Looks a bit like coral * Very common in tide pools! “Crustose” or “Leafy” type- still has encrusting type hard outer armor Brown Algae- “Phaeophyta-” Pigments intermediate (between reds and greens) and very diverse- • A Uniquely Marine group • Contain the “kelps”- among most “advanced” of all alga Offshore: Brown algae (kelp) (Macrocystis) forests of the •Extensive growth in cold, high nutrient near-shore environments. •Grow in water 20-40 m depth. •Fasten to hard substrate with holdfast. •Gas-filles floats (pneumatocysts) •Highly productive –grow 6-25 cm/day •Eaten by sea urchins •Support extensive diverse Brown Algae- (Fucus sp.) 2. Inter-tidal :

Almost all are “

- A main evolutionary division in animals:

Invertebrates vs. : Invertebrates vs. Vertebrates: What separates the groups?

 Have “backbone” (or similar structure) or not? * eg: Hollow “Nerve Tube”- running up and down the animal. • Or “notochord” A rigid structural support, like our spine.

 proxy for complex nervous system. Amazingly diverse adaptations!

Some Major groups

- Mollusks (squid, snails, ) - Crustaceans (= , shimp- BUT also ! ) - Echinoderms (, sea cucumbers, dollars) - Coelenterates (jellyfish, anemones, corals) Adaptations: Some modes of making a living

1. Grazing: ( “Grazer” = ) Adaptations : Some modes of making a living

2. Scavenging: ( = ) Filtering

Filter-feeders: can take many different forms, depending on environment.. Ambush prey with poison darts!

Predator, Secondary .. Mollusks (snails, squid, octopus, banana slugs)

*Enormous group! 100,000 + species in all environments

• All have soft, muscular “foot”: used for moving, capturing prey

• Some have shells, some don’t

• Cephalopod molluscs: squid and octopus  highly specialized predators Invertebrates: Mollusks Mollusks in Littoral: many adaptations. *Key Grazers: • Graze on all kinds of alga in littoral environments. • Often have heavy shells to protect from drying out, and from pounding surf.

But, also other important types: • Filter feeders: eg: , , etc • Hunting !: small rock snail species which drill into prey and eat them! Mussels: the dominant animal in much of inter-tidal Adapted to high energy- pounding surf: 1) very tough shells 2) held to rocks by tough fibers (“bissel fibers”) “beds” of mussels form major for other animals ( “protection” from surf) Many other mollusks in littoral- many are “grazers” of alga What is this area? What is this area? Owl LimpetWhat is this area? Crustaceans Subset of: Arthropods ”jointed legs”

*Sizes: Microscopic to Huge: (Copepods to Alaskan king Crabs)

• All have jointed Legs, Eye stalks, hard body ‘armor” made from “chitin”

• All oceanic members have gills

• Very important in oceanic food webs! (both predators and prey!) Crustaceans

In Littoral environments: Important Scavengers: *Crabs, lobsters, shrimps

*But also, a real Surprise:

 Barnacles! (both sedentary and “goose- neck”)

* An interesting evolutionary story: they settled on their heads, and use adapted “feet” to filter the water! Barnacles: so common, they define most rock surfaces c o l l Barnacles a Large size p s i n g c o l l Barnacles : a Solitary p s i n g c o l l Barnacles a p s i n g c o l l Barnacles a p s i n g c o l l Barnacles a p s i n g Invertebrates: ”Echinoderms” (“spiny skin”)

(Starfish, Sand dollars, sea urchins)

*Very important marine group! Occupy almost all modes of life- from to hunters Invertibrates: ”Echinoderms”

1) Radial Symmetry

*2) Spiny skin: More obvious in some than in others… Invertebrates: ”Echinoderms”

Have Sucker- tip Tube Feet: for motion Focus on two:

A major Grazer: sea urchins

A major Predator (hunter): sea stars Purple Urchin .. Purple Urchin .. Urchin Beds…(notice anything about rocks?) Urchin hollows Blue water gold? “Uni” = roe () “Uni” sushi at Benihana Where it really comes from.. Where it really comes from.. Stars: predators Stars: mussel predators Stars limit mussel distribution Cnidaria ()

•Over 6000 species of Class Hydrozoa •Sea anemones, found from the intertidal to 10,000 m •Capture prey with stinging nematocysts •Same phylum as corals Inter-tidal: Sea Anemones

–Giant Green Sea Anemone Sunburst and aggregating anemones Giant green anemones Anemone fight! Giant green anemones: mussel predators? One more Special Adaptation: How can an animal get more food (especially in a low food environment) 5. : (ie teamwork)

Zooxanthellae: A dinoflaggelate-

autotrophic primary producer Special Adaptations: How can an amimal get more food (especially in a low food environment) 5. Symbiosis: (ie teamwork)

Zooxanthellae: A dinoflaggelate-

Lives symbiotically inside tissues of a range of invertibrates! Zoozanthellae symbiosis: Animal + a photosynthetic protist Zooxanthellae symbiosis: Animal + a photosynthetic protist

`“Solar Powered Slugs” END. Look for email on Friday!!!