BIO 3229G: LECTURE (1-8) EXAM NOTES 2024
Lecture 1: Base of the Animal Tree
- Defining an Animal:
o Motile at some point
o Heterotrophic – do not produce own energy; get it from others
o No rigid cell wall – this separates us from plants/fungi
o All marine phyla have a marine origin – animals started at the phylum of a marine environment
o Divided broadly into vertebrates and invertebrates
Prof does not like this kind of separation – believes there is no great divide between the 2
o Divided broadly into basal and derived animals based on body symmetry
o About 5% of animals have a backbone
Most animals are like us… we’re not very representative
o Animals – a known, established clade (a grouping, designation); there is a single common ancestor
We with all animals share a single common ancestor; metazoans = multicellular;
It is not a grouping of convenience; vertebrate vs. invertebrate would be for convenience
Noticed that we share genes with distant relatives (i.e. nematodes, arthropods, etc.)
- Life, domain, kingdom, phylum, class, order, family, genus, species
- Carolus Linnaeus (1758) = developed classification by similarity; increased similarity with decreasing rank
o Problem? Convergent evolution (i.e. bats vs. birds) – same selection pressures could create similarities
amongst very different organisms; you need to look at ancestry instead!
- Random fact: cancer affected epithelial cells looked like crab/crab cells under microscope to the British guy
that discovered cancer. That’s how it got its name…
- A phylogenetic tree = a hypothesis of the expected relatedness between organisms
o Will be different depending on authors; lumpers vs. splitters when developing trees
- Here is the TREE OF LIFE; 34 phyla of animals that the species can be grouped into
Red ones: subject to possible change
Black ones: pretty set in stone with good evidence of their
placement
Humans: are chordates
Note – Chordata is not exclusive to organisms with backbones…
Symmetry developed in the bilateria
Circularity (i.e. in starfish) is secondarily derived too
Selection can work on any level
Note – clades are NOT groupings of convenience like vertebrate
vs. invertebrate
Deuterostomia vs. Protostomia is one of the biggest splits that
we should recognize
Humans: we have symmetry; go from a single egg + sperm, to
this huge thing with general symmetry. There is asymmetry (i.e.
organs) but it is secondarily derived
Sister clades = adjacent branches basically; clumpers could
,combine these when splitters could not
, find more resources at oneclass.com
Extant Species = not-extinct; surviving have to be successful one way or another (i.e. evolution, luck)
- There is no progress in evolution; there is no end goal
- There are simply solutions that have been selected for during current problems
- “Ladder” = a bad metaphor
o Humans = nested in the middle of Animalia clade; we are not sitting outside as the ‘most developed’
- Phylum demographics and habitable zones
Porifera - Sponges
Can have small benthic form, or long chimney-styled ones
8579 extant Porifera species compared to Chordata with 50,000ish
Porifera vary in size (microscopic – about a meter)
Has hard skeleton of spicules – SiO2 or CaCO3 based
If you got rid of the spicules, you would get a softer sponge; would
resemble more of your artificial sponge
Sponge Pump – does not need to be an active process; being on
benthos, it utilizes the ocean’s natural current
BUT, it actively pumps water too; used for extraction and filter feeding
Planocytes(?) = single-collared phlagellum cells that make up the interior
of the pumping system; diagram (shown on Slide 32)
Design of sponge is simplistic in nature; very few cell types
Lacks formed organs, no nervous system, complex development is
limited
Spongeocoel = the cavity
Spicules = provide a skeletal design
Pinacocytes = outside of sponge; not linked to each other
Fun Fact: Can take 2 sponges, mix them together in
a pile of cells, sort each other, and move back into
their respective 2 types
No other animal or plant can do this apparently
find more resources at oneclass.com
, FLIP1: Cnidarian Material
Was not covered in lecture, but Professor Taylor still told us to know it
- Number of extant species as of 2014 source: 13,138
- Moon Jelly = Aurelia aurita
- The term medusa was coined by Linnaeus in 1752
- Scyphozoa: “true jellyfish”, exclusively marine, cup shape
- Hydrozoa: medusa and polyp forms, related to jellyfish and corals
- Anthozoa: no medusa stage
-
- Read over Lab 1 material
FLIP CLASSROOM MATERIAL 1
Lecture 1: Base of the Animal Tree
- Defining an Animal:
o Motile at some point
o Heterotrophic – do not produce own energy; get it from others
o No rigid cell wall – this separates us from plants/fungi
o All marine phyla have a marine origin – animals started at the phylum of a marine environment
o Divided broadly into vertebrates and invertebrates
Prof does not like this kind of separation – believes there is no great divide between the 2
o Divided broadly into basal and derived animals based on body symmetry
o About 5% of animals have a backbone
Most animals are like us… we’re not very representative
o Animals – a known, established clade (a grouping, designation); there is a single common ancestor
We with all animals share a single common ancestor; metazoans = multicellular;
It is not a grouping of convenience; vertebrate vs. invertebrate would be for convenience
Noticed that we share genes with distant relatives (i.e. nematodes, arthropods, etc.)
- Life, domain, kingdom, phylum, class, order, family, genus, species
- Carolus Linnaeus (1758) = developed classification by similarity; increased similarity with decreasing rank
o Problem? Convergent evolution (i.e. bats vs. birds) – same selection pressures could create similarities
amongst very different organisms; you need to look at ancestry instead!
- Random fact: cancer affected epithelial cells looked like crab/crab cells under microscope to the British guy
that discovered cancer. That’s how it got its name…
- A phylogenetic tree = a hypothesis of the expected relatedness between organisms
o Will be different depending on authors; lumpers vs. splitters when developing trees
- Here is the TREE OF LIFE; 34 phyla of animals that the species can be grouped into
Red ones: subject to possible change
Black ones: pretty set in stone with good evidence of their
placement
Humans: are chordates
Note – Chordata is not exclusive to organisms with backbones…
Symmetry developed in the bilateria
Circularity (i.e. in starfish) is secondarily derived too
Selection can work on any level
Note – clades are NOT groupings of convenience like vertebrate
vs. invertebrate
Deuterostomia vs. Protostomia is one of the biggest splits that
we should recognize
Humans: we have symmetry; go from a single egg + sperm, to
this huge thing with general symmetry. There is asymmetry (i.e.
organs) but it is secondarily derived
Sister clades = adjacent branches basically; clumpers could
,combine these when splitters could not
, find more resources at oneclass.com
Extant Species = not-extinct; surviving have to be successful one way or another (i.e. evolution, luck)
- There is no progress in evolution; there is no end goal
- There are simply solutions that have been selected for during current problems
- “Ladder” = a bad metaphor
o Humans = nested in the middle of Animalia clade; we are not sitting outside as the ‘most developed’
- Phylum demographics and habitable zones
Porifera - Sponges
Can have small benthic form, or long chimney-styled ones
8579 extant Porifera species compared to Chordata with 50,000ish
Porifera vary in size (microscopic – about a meter)
Has hard skeleton of spicules – SiO2 or CaCO3 based
If you got rid of the spicules, you would get a softer sponge; would
resemble more of your artificial sponge
Sponge Pump – does not need to be an active process; being on
benthos, it utilizes the ocean’s natural current
BUT, it actively pumps water too; used for extraction and filter feeding
Planocytes(?) = single-collared phlagellum cells that make up the interior
of the pumping system; diagram (shown on Slide 32)
Design of sponge is simplistic in nature; very few cell types
Lacks formed organs, no nervous system, complex development is
limited
Spongeocoel = the cavity
Spicules = provide a skeletal design
Pinacocytes = outside of sponge; not linked to each other
Fun Fact: Can take 2 sponges, mix them together in
a pile of cells, sort each other, and move back into
their respective 2 types
No other animal or plant can do this apparently
find more resources at oneclass.com
, FLIP1: Cnidarian Material
Was not covered in lecture, but Professor Taylor still told us to know it
- Number of extant species as of 2014 source: 13,138
- Moon Jelly = Aurelia aurita
- The term medusa was coined by Linnaeus in 1752
- Scyphozoa: “true jellyfish”, exclusively marine, cup shape
- Hydrozoa: medusa and polyp forms, related to jellyfish and corals
- Anthozoa: no medusa stage
-
- Read over Lab 1 material
FLIP CLASSROOM MATERIAL 1
