Coral Reef Diversity and Conservation (2012) : 2012

Tuesday, December 18, 2012

Additional classes

Hi everyone,

After checking students' schedules, we have decided the additional dates for classes as follows:

1. Tuesday, January 15th, 4th period (14:40-16:10).
2. Thursday, January 24th, 5th period (16:30-18:00).

Classrooms are not yet decided.

One or two students' schedules do not fit some of these classes, so if you cannot attend, please get the notes from the blog or another student. As attendance does not count in your mark, as long as you have notes you should be able to study for the test!

cheers,

JDR

Monday, December 17, 2012

November 28, 2012 class notes

Class notes for November 28, 2012

Recent Research: Symbiodinium introduction & diversity studies

Outline:

1. Review of Symbiodinium and coral bleaching.

2. Bleaching in Thailand, 2010.

3. Symbiodinium diversity.

Part 1: Review of Symbiodinium and bleaching.
• Dangers facing coral reefs:
• Global warming is raising the temperature of the ocean; this kills corals - “coral bleaching”.
• Also, as the oceans become more acidic, it is more difficult for corals to make their skeletons.
• Perhaps 90% of coral reefs will be dead by 2050.
• Diagram of iving tissue
• Numbers of zooxanthellate genera over time, increase in ZX genera of corals.
• More diverse than ever, showing benefits of symbioses.
• Believed to have started approximately 60 million years ago.
• Symbiodinium spp. in invertebrates holobiont=host+symbiont(s)
• Corals and symbionts
• Many shallow water corals get their energy from symbiotic zooxanthellae.
• These small animals make it possible for corals to live in the warm oceans.
• But, these symbionts are sensitive to hot ocean temperatures.
• What turns the coral white?
• As a stress response, corals expel the symbiotic zooxanthellae from their tissues
• The coral tissue is clear, so you see the white limestone skeleton underneath
• What can stress a coral?
• High light or UV levels
• Cold temperatures
• Low salinity and high turbidity from coastal runoff events or heavy rain
• Exposure to air during very low tides
• Major: high water temperatures
• Thermal stress
• Corals live close to their thermal maximum limit
• If water temperature gets 1 or 2°C higher than the summer average in many parts of the world, corals may get stressed and bleach
• NOAA satellites measure global ocean temperature and thermal stress
• How warm is warm?
• How hot do you think the ocean has to get before corals start to bleach?
• GLOBAL WARMING
• Glaciers and sea ice are melting
• World map showing levels of coral bleaching. Source: ReefBase
• Can corals recover?
• Yes, if the stress doesn’t last too long
• Some corals can eat more zooplankton to help survive the lack of zooxanthellae
• Some species are more resistant to bleaching, and more able to recover
• Can corals recover?
• Corals may eventually regain color by repopulating their zooxanthellae
• Algae may come from the water column
• Or they may come from reproduction of the few cells that remain in the coral
• Can corals recover?
• Corals can begin to recover after a few weeks
• Does bleaching kill corals?
• Yes, if the stress is severe
• Some of the polyps in a colony might die
• If the bleaching is really severe, whole colonies might die
• Bleaching in Puerto Rico killed an 800-year-old star coral colony in 2005
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• What else can stress do to corals?
• Question: what is something that happens to people when they are highly stressed?
• Bleaching and coral disease
• Coral diseases are found around the world
• High temperatures and bleaching can leave corals more vulnerable to disease
• Can quickly kill part or all of the coral colony
• Bleaching and bioerosion
• We have seen that bleaching can kill part or all of a coral colony
• Areas of dead coral are more vulnerable to bioerosion (when animals wear away the coral reef’s limestone structure)
• Storms & coral bleaching
• The same warm water that causes corals to bleach can also lead to strong storms.
• Storms: a mixed blessing
• Storms: a mixed blessing
• Each passing hurricane in 2005 cooled the water in the Florida Keys.

Part 2: Coral bleaching images from Phuket, Thailand in 2010

Corals (and many other coral reef invertebrates) are in symbiosis with Symbiodinium (zooxanthellae).
This symbiosis allows these invertebrates to live in nutrient-deficient sub-tropical and tropical waters.
Algal-animal symbioses are a successful strategy that has been repeated many times in evolution.

Weak point:

Despite the success of this symbiosis, it has one very serious weak point:

Symbiodinium are very sensitive to low and high temperatures.

<18°C, and >30°C.

Coral bleaching:

When temperatures are abnormal for the holobiont, stress occurs.

With this stress, thylakoids in Symbiodinium begin to break down; the symbiont begins to poison the host.

Corals lose their symbionts, either through cell-death, or by expelling them.

Hosts turn white = coral bleaching.

Predicting coral bleaching:

The NOAA (USA) has spent much time on predicting bleaching.

Can now predict bleaching very accurately.

These tools available for free on the internet.

SST=sea surface temperature

DHW=degree heating weeks

Daily max=expected average maximum SST for a certain day

MMM=maximum monthly mean, average temperature of the hottest month

SST anomolies, coral bleaching hot spots, degree heating weeks.

Part 3: Investigating diversity of Symbiodinium: past to present.
 What are zooxanthellae?
 Algae that live in the coral polyp’s surface layer
 Algae get nutrients and a safe place to grow
 Corals get oxygen and help with waste removal
 Corals also get most of their food from the algae
 Symbiosis overview
 Genus Symbiodinium
 Described in 1962 by H. Freudenthal.
 Within dinoflagellates.
 Was though there was one single species worldwide.

 Morphology & life cycle
 Host species
 Cnidaria (corals, jellyfish, anemone, zoanthids, octocorals).
 Mollusca (clams, snails).
 Platyhelminthes (flatworms).
 Porifera (sponges).
 Protista (forams).

 First genetic studies
 Rowan & Powers 1991.
 Utlized 18S ribosomal DNA.
 Sampled from corals & anemones.
 Found unexpected diversity!
 Recommended further genetic studies.

 Second wave of studies
 Used faster evolving DNA markers.
 Particularly ITS-rDNA.
 Even more diversity!
 Zooxanthellae clade
DNA analyses
Clade: A group composed of all the species descended from a single common ancestor
 Diversity
 Eight major clades known.
 Within each clade many subclades.
 Do not know what taxonomic level clades are equal to.
 Evolution and biogeography
 Many studies have catalogued diversity.
 Can now understand on many scales.
 Can predict evolution.
 Specific types
 Many subclades or types associate with similar hosts.
 Could be co-evolution.

 Symbiodinium in Zoanthus sansibaricus
 We sampled the same species from 4 locations.
 Each host colony was shown to associate with one subclade of Symbiodinium.
 Subclade C1/C3 was common in the north, and subclade A1 was dominant in the south.
 C1/C3 has been shown to be a dominant Indo-Pacific “generalist”, with C15 common in Porites spp., and A1 a shallow-water specialist.

In Okinawa, shallow and deep populations of Z. sansibaricus.
Shallow colonies had Symbiodinium clade A1, or C1z.
Deep colonies had different type; C1zd.
Similar results seen in hard corals.
Suggests many species of Symbiodinium.

November 21, 2012 class notes

November 21, 2012

Reverse taxonomy examples

Outline

1. Trouble-shooting: dangers of reverse taxonomy.

2. Examples of reverse taxonomy from mammals (terrestrial, marine).

3. Atlantic and Pacific corals.

4. Four species of COTS.

5. Deep-sea zoanthids.

Part 1 - dangers of reverse taxonomy

What is morphological convergence?

In response to similar selective pressures, evolutionarily distant lineages evolve in similar ways and end up resembling each other in appearance, function, or both. (wiki answers)

In other words, distinct lineages look similar morphologically.

Not to be confused with the “ghost” of molecular convergence.

Much more common than thought!

Many recent phylogenetic studies have shown morphological convergence is widespread.

Butterflies, birds, lizards, algae, trees, even zoanthids!

Famous recent examples include Atlantic and Pacific corals.

Extinct-extant convergence: Similar “shapes” or body plans have appeared many times throughout the fossil record, and may even remind us of extant species.

Cryptospecies

Many “undiscovered” large vertebrate species may yet await description (e.g. Amato et al. 1998; Dung et al. 1993).

These are from the deep sea, remote regions, or are cryptic in other ways.

One famous example is theorized to exist in mountain regions of the world.

Rarely seen, but many clues (sightings, footprints, etc).

Giant unknown hominids?

Many legends exist of “giant apes” or “hairy men”.

Common in the Himalayas (yeti) and in western North America (sasquatch).

Despite large size, very little physical evidence they exist.

Evolutionary history of Gigantopithids

These cryptospecies may have evolved from extinct Gigantopithelus (Matthiesson 1979).

Fossils of Gigantopithelus known from Asia, until 3K ybp.

Possible sister lineage to humans.

Materials and Methods

Trips made to remote regions of Nepal 1992-1995, within the Himalaya mountain range (Matthiessen & Laird 1992; 1995).

Region home to the “ye-the” or “mehti”; yeti in English (described in Herge 1960; Matthiessen 1979).

Extensive trekking, traps, and local guides utilized.

Very little concrete evidence found, although highly likely to exist in the mysterious Lo Monthang valley.

Hair samples

Hair found by local guides in Lo Monthang valley, conclusively identified by them as “mehti” hair.

Hair deposited in local temple.

In 2003, request made to Nepalese government to examine hair granted.

DNA analyses

DNA well-preserved in hair.

Used mt 12S rDNA, excellent mammal marker, with modified universal primers L1091 and H1478 (Kocher et al. 1989).

Acquired sequences aligned with 15 known mammalian groups, including homonids, chimpanzees, gorillas, whales, bovine, armadillo, and Perissodactyla (horses, rhinoceros, and zebra) sequences (all GenBank).

Resulting SOAP alignment (Loytynoja & Milinkovitch 2001) subjected to MP, NJ, and Bayes analyses (Felsenstein 1985) using PAUP v 4.0b4a (Swofford 1997).

ML consensus tree, with KH tests (Kishino & Hasegawa 1989).

Results

Yeti formed highly supported monophyly with ungulates (horses, zebra, donkey, well within Perissodactyla.

Identical mt 12S rDNA to X9547 and U02581.

Well removed from primates, and outgroups.

Conclusions:

Despite “primate” appearance, the yeti is ungulate (=related to horses).

Yeti have undergone extensive morphological convergence with primates despite being genetically distant.

This idea was first proposed in Herge 1960!

Questions

Do you believe the results? Why or why not?

What else could cause these results?

What can we learn from this?

How can we prevent such things from happening?

Part 2 - New species (marine & terrestrial)

2a. A 3rd species of elephant

Background

African elephant traditionally one species with 2 major subspecies: Loxodonta africana africana and L. africana cyclotis.

Recent research suggests may be separate species, or even 4 species.

Different DNA markers, different results.

In this study, used genomic results to analyze number of species.

Samples from Mastodon, Mammoth, Asian Elephant, two populations of African Elephant.

Results

Africa-Asia split 4.2-9.0 mya.

Based on DNA, Forest & Savanna split 2.6-5.6 mya.

Asian & Mammoth split 2.5-5.4 mya.

Conclusions:

2 species of African elephant.

Asian closely related to Mammoth!

Assumptions need re-examination.

2b. Dalebout et al. 2002. A new species of beaked whale Mesoplodon perrini sp. n. (Cetacea: Ziphiidae) discovered through mitochondrial DNA sequences. Marine Mammal Science 18: 577-608.

Introduction

• Beaked whales are rare, with cryptic lifestyles. Most never observed alive.

• 12 species described in last 100 years!

• Mesoplodon hectori common in southeast Pacific.

Materials & Methods

• 5 specimens of beaked whale stranded in California, 1977-1995.

• Thought to be M. hectori based on morphology.

• Researchers then examined 2 mt DNA markers…

Results

• Results surprisingly show five specimens not M. hectori.

• New species!

• Re-examination shows morphological differences as well.

Discussion

• Authors suggest genetic voucher material for all taxa.

• Also state there are likely 40 marine mammal species still unknown!

• Cookiecutter sharks feed on M. perrini.

• Who knows what species await description?

November 7 & 14, 2012 class notes (combined)

Class 2012.11.7 & 14 - Genetics (linked to biodiversity and conservation)

Part 1 Review

1. Introduction to genetics, diversity and conservation.

Link between diversity and conservation:

Species diversity (# of species) for many groups of animals and plants unknown - lack of taxonomy.

分類学の研究が足りないせいで、色々な生物の集団の種類多様性（種の数）がほとんど知れていない状態。

99.5% of species go extinct before we even describe them.

99.5%の種類は、分類する前に絶滅になってしまう。

Without knowledge of species, how can we protect them?

種類の分類が無いと、保全ができない。

Therefore, taxonomy and diversity VERY important.

分類学や多様性の理解が重要な研究。

BUT…

Not enough taxonomy specialists, training takes time, not good pay!

Many animals and plants are VERY hard to identify using traditional methods!

Remember that...

Biodiversity = Number of taxa (species, genera), or ecosystem types, etc.

Biodiversity = bioresources.

Bioresources = long-term economic well-being.

Conserving biodiversity is important; we need to understand baseline biodiversity.

Many “neglected taxa” remain.

History of measuring marine benthic biodiversity

Marine biodiversity less understood than terrestrial.

Many marine ecosystems have high biodiversity; particularly coral reefs.

Early biodiversity work focused on hard corals, sponges, easy to preserve taxa.

Collectors did not enter the ecosystem or observe living specimens.

Type specimens in Europe or N. America; ICZN problematic.

Currently almost all marine benthos taxa have gaps.

DNA can be used to differentiate cryptic species - example adult Astraptes spp.

There are many new methods that have helped us understand diversity:

a. SCUBA - brings scientists into marine environment

b. deep-sea subs and ROVS - same as SCUBA but deeper

c. DNA - allows us to confirm without (hopefully) bias what relations exist between organisms.

Part 2 - Genetic diversity - variety of alleles or genotypes in a group being investigated.

Overview: quick explanation of evolution. Species gradually diverge; develop unique traits. Some groups disappear, others continue to evolve. Adaptations always needed.

In order to understand phylogeny we must understand evolution:

The modern synthesis of evolution is the combination of Darwin's and Mendel's theories.

The theory underlying the modern synthesis has three major aspects:

The common descent of all organisms from a single ancestor.

全ての生き物は共通の祖先から進化した。

The origin of novel traits in a lineage.

それぞれのグループはそれぞれの特徴を持つ。

Changes cause some traits to persist while others perish.

様々な変化によって、あるグループは生き残り、あるグループは絶滅する。

DNA and phylogenetics

All cells contain DNA - the code or blueprint of life.

全ての細胞には遺伝子が入っている。遺伝子は生き物の設計図。

This code has only four different "letters": A, G, C, T.

遺伝子は４つのコードしかない。

Usual length 1,000,000 to 100,000,000,000 base pairs.

生き物のひとつの細胞にある遺伝子の長さは,000,000 to 100,000,000,000 。

Genome projects read everything in one organism, but takes time and expensive.

全ての遺伝子を読むことは時間とお金の無駄。

Many studies use one or a few markers to investigate relations.

遺伝子の短い部分だけでも系統関係が解析できる。

By collecting the same marker from different samples and then analyzing them, we can make a tree.

いくつかのサンプルから同じマーカーを読んで、並べてから、解析し系統樹を作る。

It is thought/hoped a tree is similar to how evolution occurred.

系統樹から進化が見えると思われる。

DNA may be a way to have non-specialists identify species quickly!

So, DNA tree = evolutionary tree (or so we hope)

Genetic diversity is required to adapt to changing environments (ex: Hawaiian honeycreeprs). Environments are ALWAYS changing, never static. Many methods to measure genetic diversity. Large populations usually have high diversity; small populations are a concern.

Diveristy needed, give examples we have seen - industrial melanism. Also failures to adapt - chestnut trees and Okinawan pines.

Low genetic diversity also leads to less reproductive success, more inbreeding. Ex: European royal families! Maintaining different populations important.

How do we measure genetic diversity?

1. quantative measurement - morphology. size, shape, height, weight, etc. But not due only to genes, also environment and expression. Difficult to assess. Can be done in absence of other methods, cheap.

2. deleterious alleles - results from inbreeding, i.e. flies. But not good for conservation!

3. proteins - started in 1960s, slight changes in sizes form species or individuals. Uses electrophoresis. Need blood or organs, invasive.

4. DNA - many methods, always new developments. We will discuss

c. Microsatellites - used for population studies; repeats of DNA. Development time is considerable.

In a cell, two major types of DNA we will study:

a. nuclear DNA - fast evolving in Cnidaria, slower in other animals - very general rule. More later.

他の動物と違い、刺胞動物で進化が早い

b. mitochondrial DNA - slow in Cnidaria, fast in other animals. Again generalization.

他の動物と違い、刺胞動物で進化が遅い。

Example DNA markers:

COI, cytochrome oxidase subunit 1 - mt DNA, used for many studies, much data available.

16S rDNA - mt DNA, useful in zoanthids! some indels, especially V5 region.

October 31, 2012 class notes

Coral Reef Diversity and Conservation
October 31, 2012
Introduction to the Coral Reef Ecosystems and Biodiversity

Introduction to Coral Reefs:
Outline:
1. Coral reefs (large scale)
2. Coral (the animal)
3. Biodiversity
4. Example study of human influences on coral reef (Sandin et al. 2008)

1. Coral reefs (large scale)
a. What are coral reefs? How do they form?
Biggest structures made by living organisms. GBR is 1000s of km long.
Thus we may think they are tough and permanent, but they are not, and only top thin layer is generally alive.
Existed before hard corals existed, different groups have taken turns making reefs.
Modern reefs due to symbiosis between coral and zooxanthellae, can get nutrients from water, but limited to warm clear shallow water (more on this later in another class), where they compete with macroalgae (more later).

Reefs can be geological structures, and living ecosystems.
For geology, reefs affected by oceans going up and down, changes in temp and current. Shorter scales, typhoons, tsunamis, crown-of-thorns, etc.
Even shorter; bleaching, fishing, dynamite, coral reef trade, shellfish, etc.
Recently sea level has not changed so much, resulting in reefs today, but past there were many changes. Underwater cave example even.
Many reefs are like forests, tear them down and build them up.
Anyone been diving? Different levels of shelves are often indicators of past sea levels.

b. Different types of coral reefs
Starting with Darwin, many people have attempted to classify reefs into types. Humans like to classify.
Can be classified broadly into 3 types, as Darwin did. Rainwater, pounding of waves, and coralline algae make limestone from dead corals. Often reef edges have no corals, but much coralline algae. Also rubble, which may become reef in the future. Usually brought here by waves.
1: Fringing reefs: close to coastlines, may include rocks and other things besides dead coral. Briefly describe picture. Lagoons often muddy, corals on seaward edge, much variation in communities. Often lagoons may have low species diversity, while reef slopes often have highest diversity. Explain parts of the reef. Lagoon, edge,slope, channel.
2: Barrier reefs: Basically fringing reefs but further from shore, due to changes in sea level and time etc. Made almost entirely of carbonate. Often have channels for massive currents to flow through. May be a barrier reef followed by a fringing reef.
3:Atoll: walls of a reef around a lagoon, from a sunken island. Darwin first thought of this.
Many grades between these three types. Also, platform reefs that do not fit any of the classes above. Mention deep sea reefs too.

c. Geological history of coral reefs, currents etc.
Now: Reefs found in Pacific, Atlantic, and Indian. Reefs need to be in areas over 18C, this is a good temperature for ZX, for coralline algae. Reefs are not found in areas with poor visibility, with little wave action, although corals may be found there. Need also to out-compete algae.
There is little correlation between coral species numbers and reefs, as many reefs are built by just a few species. But there is a link between reefs and overall biological diversity (more on this later).

History: known from 2 billion years ago. Explain these using timelines.
First reefs built by stromatolites (blue green algae mounds that can take up sediment), then archaeocyaths (like sponges), then corals (not modern ones) along with sponges, bryozoans.
Probably in this period the first endosymbiotic symbioses evolved.
Two types of corals: Rugose and Tabulate, but died when dinosaurs did. After this no reefs for a long time.
Modern corals appeared in Triassic, have dominated reef building since then. Show maps? Show some old extinct reefs.
In mid-cretaceous, rudist bivalves dominated, probably symbiotic, and then corals came back.
At end of dinosaurs 1/3 of families, 70% of genera became extinct. All species changed!
More recent: Diversity levels have recovered. More diversity with zooxanthellate genera. Results of land shifting and old distributions show that Atlantic genera are much older than Pacific. This does not mean evolution was faster, based on previous patterns and the Tethys Sea.
Closure of Panama very important. No species of corals and few genera shared between Indo-Pacific and Atlantic. Even if many animals look the same, very few shared!

2. Coral (the animal)

a. Corals are part of
Cnidaria - animals that have one hole that serves as both mouth and anus. This is surrounded by tentacles. All Cnidaria and only cnidarians have nematocysts, defense and feeding. Two main shapes, polyp and medusa. Life cycle alternates between these two shapes; main for corals is polyps, main for jellyfish is medusae.

Anthozoa = includes octocorals and hexacorals.
Hexacorallia = includes corals, anemones, zoanthids, corallimorphs, antipatharians and cerianthids. Have mesenteries in multiples of 6.

Corals - may be colonial or solitary, zooxanthellate or azooxanthellate. Zooxanthellate colonial species responsible for making coral reefs. Polyps (living tissue) surrounded by calcium carbonate skeleton. Classification traditionally uses skeletal characteristics; color and size also used. Polyps include a mouth and oral disk surrounded by tentacles, as well as zooxanthellae (Symbiodinium spp.; abbreviated here as ZX=zooxanthellae).
Skeletons have much microstructure, important for many other animals as homes, especially when coral dead. Refuge from predators etc. Many types of corals - show pictures of these.

Also, zoanthids - related order to corals. Colonial like corals, soft like anemones. Many species have ZX. Very variable morphology even within species.

b. When understanding coral or other cnidarians on the reef, please remember that the holobiont is important.
Holobiont = host (animal) + ZX + bacteria, viruses, etc. Host may be same species, but if ZX are different, this has implications for biology and ecology of holobiont.

ZX are dinoflagellates with chlorophyll. Live inside host, give energy from sunlight to host.
ZX look similar, thought to be one species, but DNA etc. have revealed diversity, now 8 clades (A to H). Most ZX sensitive to high ocean temperatures. Usually 30C is considered a threshold. Different clades or subclades may have different physiology. ZX thylakoids degrade at hot temperatures, causing coral bleaching. Also can happen at low (<15C).
Research example: Zoanthus sansibaricus at different locations in Japan has different ZX clades!

c. Dangers facing coral reefs: Bleaching, acidification (will discuss this more in another class taught by Kurihara-sensei). Perhaps 90% of reefs dead by 2050, NOAA says 60% by 2030.

d. Species diversity for many organisms unknown. 99.5% of species go extinct before we identify them. Without knowledge of species how do we protect them? Taxonomy and diversity study important. but... training takes time, pay is poor, and many organisms VERY hard to identify in traditional methods.

3. Biodiversity;
a. Less than 0.2% of the earth, 25% or more of the ocean’s species! 10% of fish caught. Protect land as breakwaters, and valuable for tourism. All of this despite low nutrients and compounds in the surrounding water.
Corals make very complex structures thanks to their skeletons. Greatly increase amount of habitable areas, or niches, for many different species. Explain about specialized animals, use zoanthids and shogun ebi as examples.
Much problem trying to calculate actual surface area. For macroorganisms, factors of at least 15 (Dahl 1973). Much greater for microorganisms. And this is on the surface alone!

b. Diversity? How to measure it?
Biodiversity=number of species or genera, OTUs (operational taxonomic units)
Coral reefs <0.2% of the earth's surface, 25-50% of marine species.
Reefs increase surface area, 15X for large animals, more for smaller. More niches = more specialized animals.
Discuss before scuba and ideas at that time
First corals where collected in 1700s when scientific interest began, and first cataloguing. Increased greatly in 1800 and early 1900s. Museums and names.
Corals were particularly easy, as they could be preserved. So, along with fish and sea mammals and macroalage, very extensively documented.
Problems: no observation of living things in situ, no idea of variance, differ from place to place, so many incorrect names.
But, according to ICZN, these names MUST be correct, so we have continued on with bad ideas.
Other animals were largely ignored until 1800s or 1900s, such as anemones, zoanthids, corallimorphs, etc.
Many understudied groups are finally getting reexamined today, along with corals!
"New" techniques: SCUBA, submersibles, molecular techniques, have allowed a re-examination of biodiversity.
Often, "reverse" taxonomy, using DNA to identify specimens of interest, then going back to look at morphology.

4. Wrap-up using Sandin et al. (2008): Just how much biomass was on reefs before humans? What is a healthy reef? Line Islands study.
Recent papers, including the one from which handout came from (Sandin et al. 2008), show that the biomass of coral reefs may be inverted. Healthy reefs have 85% of fish biomass in sharks!! Go over paper quickly.
This has sent researchers back to old papers and accounts.
Discuss old papers where so many sea turtles
Early Atlantic explorers running aground on sea turtles.
Numerous shark stories of huge numbers of sharks.
Even in Okinawa, giant clams over 100 kg. The sea is richer than we can imagine in untouched places, but we have never seen or almost never will see. We are missing so-called “baseline” data, and now a race to get some!

Show images from Bonotsu 2011 and destroyed coral reef.

Emphasize the link between conservation and biodiversity.

VI. Recommended reading (bold in particular):
1. SA Sandin et al. 2008. Baselines and Degradation of Coral Reefs in the Northern Line Islands. PloS One 3 (2) e1548:1-11.
2. EA Dinsdale et al. 2008. Microbial Ecology of Four Coral Atolls in the Northern Line Islands. PloS One 3 (2) e1584: 1-17.
3. N Knowlton, JBC Jackson. 2008. Shifting Baselines, Local Impacts, and Global Change on Coral Reefs. PloS Biology 6 (2) e54:215-220.
4. Corals of the World – JEN Veron. 2000. Australian Institute of Marine Science. Melbourne.