Biodiversity and Ecology of Invertebrates
ALGEMENE INFO (zie canvas)
Onderwijstalen
Engels, Nederlands→ HOC + WPO: F.6.55
Onderwijsteam
Joren SNOEKS
Thomas Merckx
Marc Kochzius (titularis),
Onderdelen en contacturen
26 Hoorcollege, 26 Werkcolleges, practica en oefeningen, 26 Zelfstudie en externe werkvormen
Inhoud
Dit opleidingsonderdeel behandelt de evolutieve oorsprong en verwantschappen van de grote
evertebraatgroepen, b.v.
• Porifera
• Cnidaria
• Platyhelminthes
• Nematoda
• Annelida
• Arthropoda
• Mollusca
• Echinodermata
• Tunicata
Het opleidingsonderdeel geeft een overzicht van hun diversiteit in vorm, functie, en gedrag. Tijdens de
hoorcolleges zal aandacht besteed worden aan classificatie, morfologie, fylogenetische
verwantschappen en hun ecologie.
Het practicum is erop gericht de opgedane theoretische kennis in praktische competenties om te zetten.
De student leert hierbij vooral determineertechnieken en tekeningen van de morfologie en anatomie van
evertebraten te maken.
Twee excursies zijn gepland: één naar de Zoniënwoud en één naar de Noordzee met een onderzoeksschip.
Leerresultaten
Algemene competenties
In dit opleidingsonderdeel leer je:
• zelf ontwikkelen van eigen leerproces
• in groepsverband werken
• gegevensbronnen ter aanvulling van de leerstof opsporen
• een analyse en synthese maken van de leerstof
• een biologische vraagstelling formuleren
• de verworven kennis presenteren en overbrengen
Beoordelingsinformatie
Examen Mondeling bepaalt 50% van het eindcijfer
Examen Schriftelijk bepaalt 30% van het eindcijfer
HOC Presentatie bepaalt 20% van het eindcijfer
Aanvullende info mbt evaluatie
De evaluatie zal op twee onderdelen gebaseerd zijn:
HOC 70%: mondelinge presentatie (20%), mondeling examen (50%)
WPO 30%: tekeningen en verslagen
1
,Biodiversity and Ecology of Invertebrates
Structure of each chapter
General information
Design diversity
• General structures
• Cellular structures
• Forms
• Classes
Specials
2
,Biodiversity and Ecology of Invertebrates
INLEIDENDE LES: duiding van biodiversiteit en ecologie bij invertebraten
What is biodiversity?
Biodiversity (1986)= “...the sum total of all biotic variation from the level of genes to ecosystems”
(Purvis and Hector 2000)
Biodiversity: 3 hierarchical levels (Watson et al. 1995):
Ø Ecological diversity= variety of different ecosystems
Ø Organismal diversity= number of species
Ø Genetic diversity= genetic difference within and between species
Numbers
→ 1.75 million known species
→ 7 and 20 million are estimated to still to be discovered
Datatbases met soorten: FishLife, WoRMS, … (probleem met schatten is geen gezamenlijke database)
→estimated total extant [existing= not extinct] species
Importance of biodiversity
→goods and services: essential to human societies
In economical terms:
-world’s natural capital and ecosystem services: US$ 33 trillion per year (2/3 from oceans)
-coastal ecosystems: US$ 12.5 trillion per year (fisheries, nutrient cycling, coastal protection, and
recreation for human societies) (Costanza et al. 1997)
*e.g. marine fisheries was about 85.8 million tonnes in 2004 (FAO 2007), developing countries earned
approximately US$ 20.4 billion from marine fisheries (FAO 2007)
Threaths to biodiversity?
→Extinction rates (vertebrates, vascular plants): ~50- 100 x higher than natural background (=without
human influence)
!!!extinction caused by human activities is not a recent phenomenon; it already started in prehistoric
times, e.g. when humans colonised the islands of the Indo-Pacific, accompanied by pigs, dogs, and rats
→5-20 % known species are threatened with extinction
→1/4 world’s bird species may have gone extinct during prehistoric times
→650 plant and >480 animal species got extinct since 1600
(Watson et al. 1995)
3
,Biodiversity and Ecology of Invertebrates
Wat is a species?
Many definitions
→conclusion: species are difficult to establish/ document
INTEGRATED PHYLOGENY (=combining multiple methods for defining a species)
*e.g. Giant Clams~ Tridacna sp. (bedreigde diersoort)
Uknown clam→ research on different characteristics (different definitions)
1. visual comparison to 3 other known species
suspicion of new species
2. Morfological species concept: plotting morphological similarities
MDS-analysis (Multi-Dimensional Scaling) based on 5 shell measurements
? prob. new species because not much overlap
-> new name: Tridacna costata sp. Nov. (New.)
3. Biological species concept: spawning frequency test
Different spawning times
-> prob. different species
4
,Biodiversity and Ecology of Invertebrates
4. Phylogenetic species concept: phylogenetic tree based on mitochondrial 16S rDNA sequences
No connection via mitochondrial DNA
so not in the same species
RESULT: on basis of morphological, ecological an phylogenetic research: new species
BUT: stay critical, why wasn’t such a big clam on a accessible area discovered?
→ look in history books it might already have been discovered but not standardized in recent data
In 19th century this clam was discovered and named Tridacna squamosina (because it looks like the
squamosa) and has now been given a junior synonym Tridacna constata
Other method: DNA barcoding of giant clams Velkeneers et al. (2022)
→barcoding of known markergene (chosen per species) for giant clams (CO1=cytochrome oxidaze 1)
inside of mitochondrial DNA→ maternal connection to other species
Make sequence of said gene to compare to other sequences of this marker gene, if not in the database,
possibly a new species
BUT: stay critical it’s possible that some known species aren’t yet sequenced or saved in databases
*e.g. Research: number of species giant clams through the years
-research of past done via heaps of shells and “leftovers” trown back into the sea by fisheries (stays in
relative heaps during the years)
-conclusion: collapse of species (why: ?)
5
,Biodiversity and Ecology of Invertebrates
L1: general introductional knowlegde
Three of Life: cellular life
Phylogenomic tree of life
3 domain theory → Consensus view on evolutionary relationships within the three domains of cellular life
2 domain theory → Eocyte hypothesis: some Archaea are closer to Eukarya (= Eukaryota) then to other
Archaea, archaea becomes parafyletic
EXAM: will be asked, both version with all the fyla
MORFOLOGICAL/DEVELOPMENTAL PHYLOGENY MOLECULAR PHYLOGENY
=bryzoa
=bryzoa
Characteristics
▪ Body symmetry
Radiata Bilateralia
Radial symmetry Bilateral symmetry
-Diploblastic animals: 2 germ layers Triploblastic animals:3 germ layers
*ectoderm *ectoderm
*endoderm *endoderm
* mesoderm
6
,Biodiversity and Ecology of Invertebrates
▪ Cavities
No cavitie Developed by schizocoelie of enterocoelie
Acoelomate (Eu)coelomate= REAL coelomate Pseudocoelomate
Triploblastic -Fluid-filled coelom lined by -Coelom not fully lined
organisms mesoderm by mesoderm (only 1
-Blastocoel filled side)
with mesodermal
tissue
▪ Development
Protostomia Deuterostomia
-Spiral cleavage -Radial cleavage
-diagonal -parallel/perpendicular
-determined -undetermined (totipotent)
Split=death Split= twins
Schizocoeli Enterocoeli
Protostomia= mouth first (out blastophorus) Deuterostomia= mouth second, anus first
(out blastophorus)
7
, Biodiversity and Ecology of Invertebrates
L2: Porifera [parazoa]
Porifera=Sponges
→drawings of Heckel (art nouveau influence by organic patterns such as Heckel’s book: Art forms of
nature)
General information
Difficult to identify species just from picture→ spiculae
-fylum porifera
-Metazoa (mulitcellullaire): parazoa (niet-gedifferentieerd: omnipotente cellen) (eumetozoa)
-8,000 described species
Completely aquatic: Mostly marine, only about 150 in freshwater
-Demospongia: 80-90 % of all species; siliceous spicules and/or spongin
-Calcarea: 500 extant species; marine; calcite spicules
-Hexactinellidae (glass sponges) : approximately 400 extant species; siliceous spicules
*hypothesis of phyla’s → Phylogenies are mostly always hypothesis
Different growth forms, all use chemical warfare to compete for territory
*massive sponges
*encrusting sponges
*boring sponges (‘drill’ inside the substrate, live inside, bio-eroding, creating there own crevice’s)
8
ALGEMENE INFO (zie canvas)
Onderwijstalen
Engels, Nederlands→ HOC + WPO: F.6.55
Onderwijsteam
Joren SNOEKS
Thomas Merckx
Marc Kochzius (titularis),
Onderdelen en contacturen
26 Hoorcollege, 26 Werkcolleges, practica en oefeningen, 26 Zelfstudie en externe werkvormen
Inhoud
Dit opleidingsonderdeel behandelt de evolutieve oorsprong en verwantschappen van de grote
evertebraatgroepen, b.v.
• Porifera
• Cnidaria
• Platyhelminthes
• Nematoda
• Annelida
• Arthropoda
• Mollusca
• Echinodermata
• Tunicata
Het opleidingsonderdeel geeft een overzicht van hun diversiteit in vorm, functie, en gedrag. Tijdens de
hoorcolleges zal aandacht besteed worden aan classificatie, morfologie, fylogenetische
verwantschappen en hun ecologie.
Het practicum is erop gericht de opgedane theoretische kennis in praktische competenties om te zetten.
De student leert hierbij vooral determineertechnieken en tekeningen van de morfologie en anatomie van
evertebraten te maken.
Twee excursies zijn gepland: één naar de Zoniënwoud en één naar de Noordzee met een onderzoeksschip.
Leerresultaten
Algemene competenties
In dit opleidingsonderdeel leer je:
• zelf ontwikkelen van eigen leerproces
• in groepsverband werken
• gegevensbronnen ter aanvulling van de leerstof opsporen
• een analyse en synthese maken van de leerstof
• een biologische vraagstelling formuleren
• de verworven kennis presenteren en overbrengen
Beoordelingsinformatie
Examen Mondeling bepaalt 50% van het eindcijfer
Examen Schriftelijk bepaalt 30% van het eindcijfer
HOC Presentatie bepaalt 20% van het eindcijfer
Aanvullende info mbt evaluatie
De evaluatie zal op twee onderdelen gebaseerd zijn:
HOC 70%: mondelinge presentatie (20%), mondeling examen (50%)
WPO 30%: tekeningen en verslagen
1
,Biodiversity and Ecology of Invertebrates
Structure of each chapter
General information
Design diversity
• General structures
• Cellular structures
• Forms
• Classes
Specials
2
,Biodiversity and Ecology of Invertebrates
INLEIDENDE LES: duiding van biodiversiteit en ecologie bij invertebraten
What is biodiversity?
Biodiversity (1986)= “...the sum total of all biotic variation from the level of genes to ecosystems”
(Purvis and Hector 2000)
Biodiversity: 3 hierarchical levels (Watson et al. 1995):
Ø Ecological diversity= variety of different ecosystems
Ø Organismal diversity= number of species
Ø Genetic diversity= genetic difference within and between species
Numbers
→ 1.75 million known species
→ 7 and 20 million are estimated to still to be discovered
Datatbases met soorten: FishLife, WoRMS, … (probleem met schatten is geen gezamenlijke database)
→estimated total extant [existing= not extinct] species
Importance of biodiversity
→goods and services: essential to human societies
In economical terms:
-world’s natural capital and ecosystem services: US$ 33 trillion per year (2/3 from oceans)
-coastal ecosystems: US$ 12.5 trillion per year (fisheries, nutrient cycling, coastal protection, and
recreation for human societies) (Costanza et al. 1997)
*e.g. marine fisheries was about 85.8 million tonnes in 2004 (FAO 2007), developing countries earned
approximately US$ 20.4 billion from marine fisheries (FAO 2007)
Threaths to biodiversity?
→Extinction rates (vertebrates, vascular plants): ~50- 100 x higher than natural background (=without
human influence)
!!!extinction caused by human activities is not a recent phenomenon; it already started in prehistoric
times, e.g. when humans colonised the islands of the Indo-Pacific, accompanied by pigs, dogs, and rats
→5-20 % known species are threatened with extinction
→1/4 world’s bird species may have gone extinct during prehistoric times
→650 plant and >480 animal species got extinct since 1600
(Watson et al. 1995)
3
,Biodiversity and Ecology of Invertebrates
Wat is a species?
Many definitions
→conclusion: species are difficult to establish/ document
INTEGRATED PHYLOGENY (=combining multiple methods for defining a species)
*e.g. Giant Clams~ Tridacna sp. (bedreigde diersoort)
Uknown clam→ research on different characteristics (different definitions)
1. visual comparison to 3 other known species
suspicion of new species
2. Morfological species concept: plotting morphological similarities
MDS-analysis (Multi-Dimensional Scaling) based on 5 shell measurements
? prob. new species because not much overlap
-> new name: Tridacna costata sp. Nov. (New.)
3. Biological species concept: spawning frequency test
Different spawning times
-> prob. different species
4
,Biodiversity and Ecology of Invertebrates
4. Phylogenetic species concept: phylogenetic tree based on mitochondrial 16S rDNA sequences
No connection via mitochondrial DNA
so not in the same species
RESULT: on basis of morphological, ecological an phylogenetic research: new species
BUT: stay critical, why wasn’t such a big clam on a accessible area discovered?
→ look in history books it might already have been discovered but not standardized in recent data
In 19th century this clam was discovered and named Tridacna squamosina (because it looks like the
squamosa) and has now been given a junior synonym Tridacna constata
Other method: DNA barcoding of giant clams Velkeneers et al. (2022)
→barcoding of known markergene (chosen per species) for giant clams (CO1=cytochrome oxidaze 1)
inside of mitochondrial DNA→ maternal connection to other species
Make sequence of said gene to compare to other sequences of this marker gene, if not in the database,
possibly a new species
BUT: stay critical it’s possible that some known species aren’t yet sequenced or saved in databases
*e.g. Research: number of species giant clams through the years
-research of past done via heaps of shells and “leftovers” trown back into the sea by fisheries (stays in
relative heaps during the years)
-conclusion: collapse of species (why: ?)
5
,Biodiversity and Ecology of Invertebrates
L1: general introductional knowlegde
Three of Life: cellular life
Phylogenomic tree of life
3 domain theory → Consensus view on evolutionary relationships within the three domains of cellular life
2 domain theory → Eocyte hypothesis: some Archaea are closer to Eukarya (= Eukaryota) then to other
Archaea, archaea becomes parafyletic
EXAM: will be asked, both version with all the fyla
MORFOLOGICAL/DEVELOPMENTAL PHYLOGENY MOLECULAR PHYLOGENY
=bryzoa
=bryzoa
Characteristics
▪ Body symmetry
Radiata Bilateralia
Radial symmetry Bilateral symmetry
-Diploblastic animals: 2 germ layers Triploblastic animals:3 germ layers
*ectoderm *ectoderm
*endoderm *endoderm
* mesoderm
6
,Biodiversity and Ecology of Invertebrates
▪ Cavities
No cavitie Developed by schizocoelie of enterocoelie
Acoelomate (Eu)coelomate= REAL coelomate Pseudocoelomate
Triploblastic -Fluid-filled coelom lined by -Coelom not fully lined
organisms mesoderm by mesoderm (only 1
-Blastocoel filled side)
with mesodermal
tissue
▪ Development
Protostomia Deuterostomia
-Spiral cleavage -Radial cleavage
-diagonal -parallel/perpendicular
-determined -undetermined (totipotent)
Split=death Split= twins
Schizocoeli Enterocoeli
Protostomia= mouth first (out blastophorus) Deuterostomia= mouth second, anus first
(out blastophorus)
7
, Biodiversity and Ecology of Invertebrates
L2: Porifera [parazoa]
Porifera=Sponges
→drawings of Heckel (art nouveau influence by organic patterns such as Heckel’s book: Art forms of
nature)
General information
Difficult to identify species just from picture→ spiculae
-fylum porifera
-Metazoa (mulitcellullaire): parazoa (niet-gedifferentieerd: omnipotente cellen) (eumetozoa)
-8,000 described species
Completely aquatic: Mostly marine, only about 150 in freshwater
-Demospongia: 80-90 % of all species; siliceous spicules and/or spongin
-Calcarea: 500 extant species; marine; calcite spicules
-Hexactinellidae (glass sponges) : approximately 400 extant species; siliceous spicules
*hypothesis of phyla’s → Phylogenies are mostly always hypothesis
Different growth forms, all use chemical warfare to compete for territory
*massive sponges
*encrusting sponges
*boring sponges (‘drill’ inside the substrate, live inside, bio-eroding, creating there own crevice’s)
8
