Evolution of environmental traits in reef algae

HEROEN VERBRUGGEN, UNIVERSITY OF MELBOURNE

Talk contents

Niche evolu1on + impact on biodiversity

Limestone-‐boring algae

Vanessa Marcelino Lennert Tyberghein Joana Costa

Niche Evolu,on Boring Algae

Zachos et al. 2008. Nature 451: 279

Evolu1on of clima1c niches – context

Global SST decreases through Cenozoic

Bio-‐ORACLE

Tyberghein et al. (2012) Glob Ecol Biogeogr 21: 272

Halimeda – species diversity map

map by Tom Schils

SST affini1es modeled along tree

C1 C2 C3 C4 C5

Verbruggen et al. (2009) Global Ecol. Biogeogr. 18: 393-‐405

How does evolvability of thermal niches come about?

Marcelino et al. – unpublished

Halimeda – microhabitat evolu1on

Exposed microhabitat Sheltered microhabitat

Marcelino et al. – unpublished

Microhabitat specializa1on as exapta1on for macroecological shi]s

sheltered exposed

Can niche evolu1on explain geographical paêrns of diversity?

low

high

Tiênsor et al. (2010) Nature 466: 1098-‐1107 — Jablonski et al. (2006) Science 314: 102-‐106

The notorious LDG

Decreasing species diversity from tropics to poles

Many, many, MANY explana1ons proposed

Evolu1onary perspec1ve: species turnover

Kerswell (2006) Ecology 10: 2479-‐2488

Bimodal la1tudinal diversity paêrn

Highest diversity in temperate regions

Do the same evolu1onary processes hold?

…but for seaweeds

LDG and diversifica1on

sea surface temperature

diversifica1o

n

diversifica1o

n

cold warm

sea surface temperature

cold warm int. int.

cold int. warm int. cold cold int. warm int. cold

λ = sigmoid ( SST ) λ = hump ( SST )

Codium -‐ Species diversity map

map by Tom Schils

Codium – evolu1on of SST affini1es C1 C2 C3

Verbruggen et al. – unpublished

λ = constant

SST affinity of lineage

Codium – diversifica1on and SST

2,500.8

ΔAIC = 0

diversifica1o

n


AIC

λ = constant λ = hump ( SST )

diversifica1o

n

SST affinity of lineage SST affinity of lineage


2,500.8 2,485.1 AIC

ΔAIC = 0 ΔAIC = –15.7


λ = sigmoid ( SST ) λ = constant λ = hump ( SST )

diversifica1o

n

SST affinity of lineage SST affinity of lineage SST affinity of lineage


2,500.8 2,482.5 2,485.1 AIC

ΔAIC = 0 ΔAIC = –15.7 ΔAIC = –18.3


Codium – temperate flora is old C1 C2 C3


Conclusions and perspec1ves •  Conclusions so far:

–  Niche shi]s vs. niche conserva1sm –  Evolvability and the microhabitat –  Diversifica1on relates to SST –  Diversifica1on relates to evolvability

•  Perspec1ves 1 –– Joana's PhD –  Scale up: genus ➟ order –  Harder ques1ons: adapta1on + interac1ons

•  Perspec1ves 2 –– Will's PhD –  Integra1on with evolu1onary ecology

•  Perspec1ves 3 –– go wide –  trace element u1liza1on & other physiological features –  genome content –  life history traits & diversifica1on

Limestone-‐boring algae

Verbruggen & Tribollet. 2011. Curr. Biol. 21: R876

Boring algae: What are they?

-‐  Common in stony corals skeletons -‐  Underneath the living coral 1ssue

-‐  Algae, cyanobacteria (and fungi) -‐  Siphonous green algal genus

Ostreobium is the most common boring algae

Photo: S. Berrin

Boring algae: What do they do?

-‐  Bioerosion Tribollet. Current Developments in Bioerosion. 2008.

CaCO3 dissolu1on & a^rac1ng grazers

-‐  Low light photosynthesis Koehne et al. Biochim Biophys Acta – BioenergeFcs. 1999.

Absorp1on in far red

-‐  Coral bleaching Fine & Loya. Proc Royal Soc B. 2002.

Provide alterna1ve source of energy

-‐  Holobiome Rosenberg et al. Nature Reviews Microbiol. 2007.

Corals adapta1on and resilience

Tribollet. Cu

rren

t Develop

men

ts in Bioerosion.2008.

Boring algae: biodiversity

Taxonomy: 5 Ostreobium species

O. constrictum O. duerdenii O. okamurae O. reineckii O. quekeSi

Molecular survey in Eilat

Gutner-‐Hoch & Fine. Coral Reefs. 2011

2 species of coral seven clades of Ostreobium some rela1on to depth

Problem & Goals

•  Problem: – Unrecognized biodiversity – Are they equivalent?

•  Goals: – biodiversity assessment –  relate endolith community structure to environment

Environmental sequencing approach Proof of concept study: 3 locali1es => Guam, Mariana Islands 10 samples:

7 Porites rus 1 Porites cylindrica 1 Psammocora conFgua 1 Acropora muricata

amplifica1on of 3 loci, each ca. 300 bp

-‐ UPA (part of plas1d 23S gene)

=> anything with a proper plas1d genome

-‐ tufA => green algae

-‐ rbcL => green algae

Environmental sequencing approach

Quality filtering

Opera1onal Taxonomic Units (OTUs)

Assign Taxonomy (RDP)

Diversity analyses

High-‐throughput sequencing:

mul1plexed library

Ion Torrent => 3 million sequences

10 samples x 3 loci => 100,000 reads each

What's in there? Results for UPA

At 90% similarity (≈ genus level):

608 OTUs

Chlorophytes

Cyanobacteria

Rhodophytes

Other eukaryotes

Unknown

336 unknown OTUs

144 Chlorophytes OTUs 30 Bryopsidales

How dominant are they?

Unknown

Rhodophytes

Chlorophytes

Cyanobacteria

Other Eukaryotes

Propor,on of reads matching main taxonomic groups:

S1

S2

S3

S4

S5

S6

S7

S8

S9

S10

Green algae highly dominant. With tufA marker, we find 121 species of Ostreobium.

Correlates of community composi1on

Principal Coordinates Analysis (PCoA)

on UniFrac distance matrix

=> 3D representa1on of 1st, 2nd and 3rd PCs

Polaris

CRMS

Sampling sites

green algae frac1on with tufA marker

Correlates of community composi1on

Pillar shape

Plate shape

PCoA plot on UniFrac distance matrix

Host morphology

PC1 (30%)

PC2 (24%)

PC3 (16%)

green algae frac1on with tufA marker

Conclusions and perspec1ves

•  Huge unknown biodiversity of boring algae species ➟ higher taxa

•  Not homogeneously distributed –  Depth (Eilat study) –  Spa1al –  Host colony morphology

•  Perspec1ves –– Vanessa's PhD –  Beêr sequencing protocol –  Hierarchical sampling design

➟ patchiness –  Depth, human impact, CO2 gradients –  Niche models

Photo: L. Stravias

More perspec1ves

Genome biology Photobiology Bioerosion

Vanessa Marcelino Lennert Tyberghein Joana Costa

Niche Evolu,on Boring Algae

Collectors: Rob Anderson Elizabeth Bandeira John Bolton Francis Bunker Olivier Dargent Laury Dijoux Kya^ Dixon Rainbo Dixon

Stefano Draisma Cindy Fernandez Suzanne Fredericq Wilson Freshwater Fred Gurgel John Huisman Lisa Kirkendale Gerry Kra]

Chris Lane Line Le Gall Diane Li^ler Mark Li^ler Lydiane Mavo Frederic Mineur Klaas Pauly Claude Payri

Willem P.v.Reine Craig Schneider Gary Saunders Thomas Sauvage Tom Schils Heather Spalding John West … many others …

Collaborators: Sofie D’hondt Chris Drake Nick Eloot Wiebe Kooistra Frederik Leliaert Diane Li^ler Mark Li^ler Steve LoDuca

Chris Maggs Antoine N'Yeurt Fa1ma Oliveira Mariana Oliveira Claude Payri Gary Saunders Thomas Sauvage Tom Schils

Satoshi Shimada Thomas Silberfeld Heather Spalding Frederique Steen Ana Tronholm Andy Vierstraete Brian Wysor Rick Zechman