Exam 3 Dr.Wood Evolutionary Bio

coacervate droplets

coacervate droplets

• Non-living organic chemicals can form colloidal protein molecules that when mixed with other compounds tend to clump together

• balls of molecules that float in water

Proteinoid microspheres

form when heated amino acids and they become mixed with water.

Prebiotic earth is character as :

15% water vapor and 21% O2

The major finding of Stanley Miller’s paper of 1953 and its importance to the evolutionary theory

discovered how amino acids could have existed on primitive earth

The big bang explosion

occurred about 15 billion years ago, and started the beginning of the universe

The age of the earth

4.5 billion years old

eukaryotic

Which organism stem do humans belong to?

What is a rough ordering of energy acquisition?

Anaerobic utilization of inorganic chemicals → fermentation → Photosynthesis → Respiration

What is archaebacteria and its 3 main groups?

1. Methanogens

2. Halophiles

3. Thermophiles

Thermophiles

aerobic organisms

Halophiles

aerobic organisms that have a very simple photosynthetic system based on the pigment of rhodopsin

Methanogens

anaerobic organisms that reduce CO2 for energy

What is Eubacteria?

It includes most pathogenic species and acquires its energy through photosynthesis. This can be done both aerobically and anaerobically.

What is the Endosymbiotic Theory?

It states that the eukaryotic cell is a community of prokaryotic cells. It also states that eukaryotes evolved gradually through a series of mutualistic relationships that developed between prokaryotes.

What is the Three Viruses, Three Domains hypothesis and what did it lead to?

Patrick Forterre's "three viruses, three domains" hypothesis suggests that viruses played a crucial role in the transition from RNA to DNA and the evolution of Bacteria, Archaea, and Eukaryota. This viral infection process contributed to the divergence of the three domains of life.

What supports the RNA world hypothesis?

It is supported by the observation that many of the most critical components of cells are composed of mostly or entirely RNA. This indicates that the RNA in modern cells is an evolutionary remnant of the RNA world that preceded ours. It is also supported by RNA’s ability to store, transmit, and duplicate genetic information, as DNA does.

What is the RNA world hypothesis?

It proposes that self-replicating RNA molecules are precursors to current life, which is based on DNA, RNA, and proteins.

According to Pioneer Organism, how was the fundamental idea of the origin of life

Pressure and heat a water flow dissolved volcanic gasses to 100 C. Pass the flow over catalytic transition metal solids. Wait and locate the formation of catalytic metallo-peptides.

mitochondria orgin

Invasion of a large cell by a purple bacterium capable of respiration develops into :

Chloroplast origin

Invasion of a cell by photosynthetic cyanobacterium - this provided photosynthetic capability in a cell that was already capable of respiration

iron-sulfur world theory (Günter Wächtershäuser & Karl Popper )

life may have formed on the surface of iron-sulfide minerals and it was developed by retrodiction from extant biochemistry in conjunction with chemical experiments.

Oparin-Haldane hypothesis

There had been a gradual prebiotic evolution of molecules followed by an aggregation of these molecules that eventually results in the self-replication of complex molecular aggregates or Life.

Alexander and Oparin and JBS proposed ?

• The idea of pre-biotic evolution

• The Oparin-Haldane Hypothesis

 difference between coevolution and cospeciation?

Coevolution is reciprocally induced evolutionary change between two or more species. Cospeciation is the phylogenetic tracking of host clades by parasite clades

Cospeciation

is the phylogenetic tracking of host clades by parasite clades

What causes cospeciation to occur?

when speciation patterns in a host are reflected in the speciation patterns of the parasites.

 gene-for-gene hypothesis

• This hypothesis states that during the evolution of a host-parasite system, complementary genetic systems are developed in which each host gene that affects defense is matched by a parasite gene that affects attack.

• The host develops defense so the parasite develops as new offense

relationships that have likely resulted from coevolutionary phenomena and what did it lead to?

Host-parasite systems led to the gene-for-gene hypothesis.

coevolution.

Reciprocally induced evolutionary change between two or more species or populations.

difference between polytypic vs monotypic/monospecific?

Polytypic is a species in which there are two or more subspecies present. Species that are not divided into subspecies are monotypic/monospecific.

sympatric

Multiple mechanisms result in one or more new species from an ancestral species with no geographic segregation of populations.

parapatric

occurs when two populations of an ancestral species start to differentiate without complete separation. They might share a small area where they interbreed but still become distinct species. 

allo-parapatric

is when two populations of an ancestral species are initially separated, then become partially different while living near each other (parapatry), and finally develop complete lineage independence.

What makes model III (allopatric)  different from models I and II?

Models I and II assume that there are two factors affecting species stability, homeostasis, and gene flow whereas model III assumes that the overriding force providing species cohesion is evolutionary stasis therefore this is the model that is applied to asexual species.

peripheral isolates ; Model II

New species arise in marginal habitats and the model is concerned with very few demes at the very edge of the species range of an ancestral species composed of many demes.

vicariant speciation ; Model I

It is the physical separation of two or more relatively large populations of a single ancestral species and how they become two separate lineages.

phylogenetic species concept altered by (McKittrick and Zink in 1988)

added that “it is the smallest diagnosable cluster and is monophyletic-group

DEME

local, stable population

How did Wiley modify the evolutionary species concept in 1978?

An evolutionary species is a single lineage of ancestor-descent populations that maintains its identity from other such lineages and which has its own evolutionary tendencies and historical fate.

 important weakness in the biological species concept

no way of dealing with asexual species because of the focus on reproductive mechanisms that pertain primarily to diploid bisexual organisms.

Main difference between allopatric and allo-parapatric speciation

allopatric speciation involves complete geographic isolation, while allo-parapatric speciation involves partial isolation with a narrow contact zone along a geographic barrier.

Phylogenetic naturalness

taxons that share a common ancestor not ancestral to any other group.

Phenetic naturalness

a taxon composed of members that resemble each other more than they resemble any non-group member.

Aristotelian naturalness

a taxon that embodies the essence of the group.

3 different types of naturalness for taxons

1. Aristotelian naturalness

2. Phenetic naturalness

3. Phylogenetic naturalness

Paralogous genes

genes that come from a gene duplication event

Orthologous genes

(When doing a phylogenetic analysis you have to work with orthologous genes because they track speciation events that you want to reconstruct)

genes between species that are homologous because of a speciation event.

2 types of gene homology

1. Orthologous genes

2. Paralogous genes

Outgroup comparison.

The character states observed in the outgroup are considered primitive when compared to those in the ingroup which would be considered derived.

a. NO

b. NO

c. use outgroups

Do the following schools of thought have polarizing characters?

a. evolutionary systematics

b. Phenetics/Numerical Taxonomy

c. Phylogenetics

a. NO

b. YES (UPGMA, neighbor)

c. yes (parsimony methods, bayesian methods, maximum likelihood algorithms)

Do the following schools of thought all use tech and algorithms?

a. evolutionary systematics

b. Phenetics/Numerical Taxonomy

c. Phylogenetics

a. Yes

b. No

c. No

Do the following schools of thought all use weighted characters?

a. evolutionary systematics

b. Phenetics/Numerical Taxonomy

c. Phylogenetics

stable system for Zoology (KPC-OFGS)

Kingdom, phylum, class, order, family, genus, species

speciation events

Evolutionary history is composed of a series of:

1. Anagenesis

2. Cladogenesis

The history of speciation involves two fundamental elements:

Anagenesis

character modification

Cladogenesis

lineage splitting

anagenesis has at least kept pace with cladogenesis

The history of speciation can be recovered if:

the generation of hypothesis and hypothesis testing

Describe Science as a process

a phylogenetic hypothesis

You cannot engage in evolutionary hypothesis testing without reference to :

1. General biology

2. comparative biology

The study of biology can be broken down into what two groups according to Nelson (1970)?

comparative biology

Which study of biology is systematics categorized as?

general biology

concerned with matters of process and mechanism

comparative biology

concerned with diversity and it’s causal explanation

General biologist

This type of investigator will typically pick the group that is best suited to demonstrate the types of processes and mechanisms he is concerned with

Comparative biologist

This type of investigator is concerned with:

1. distribution of characters among taxa

2. origination of characters

3. reasons why a particular character was retained

Systematics

concerned with the study of organismic diversity as that diversity is relevant to some specified kind of relationship thought to exist among populations, species, or higher taxa ( Wiley, 1981)

biologists are systematists

While all systematists are comparative biologists, not all comparative….

Taxonomy

related to systematics but the two words are not interchangeable.

Taxonomy

study of biological nomenclature which has as its focus the naming and assignment of particular organisms to different groups

1. attempts to recover the phylogenetic genealogical relationships among a group of organisms

2. produce classifications that exactly reflect those hypotheses of genealogical relationships

Phylogenetics is one approach to systematics that:

is a history of speciation as it has occurred on this planet

What is genealogical history when applied to the level of species and higher taxa?

Willi Hennig

Who published the original theory of phylogenetics book in 1950?

Taxon ( Wiley)

• grouping of organisms given a proper name

• grouping of organisms that could be given a proper name but is not named as a matter of convention

a group of any rank that is sufficiently distinct to be worthy of being assigned to a definite category

What did Mayr define Taxon as and is later seen as problematic?

Natural Taxon

a species or a group of species that exists in nature as the result of a unique history of descent with modification

Species

are lineages that are independent of other lineages in the sense that they may evolve independently of other such lineages

Species

What comprised of the highest level of taxonomic organization on which the processes of evolution may work?

Monophyletic group

• group that contains an ancestor and all of that ancestors descendants

• natural taxon

Clade

Another name for a monophyletic group

Paraphyletic group

• a group with no ancestor that is unique to its component species

• a group that contains an ancestor and some but not all of its descendants

• non-natural taxon

Polyphyletic Group

• a group in which that most recent common ancestor has been assigned to some other group

• the ancestor of 2 or more descendants has been left out

• non-natural taxon

Sister Group

a species or higher monophyletic taxon is hypothesized to be the closest genealogical relative of a given taxon exclusive of its ancestor

we are saying that they are hypothesized to share an ancestral species not shared by any other taxon

What do we mean when we say two taxa are sister groups?

Out Group

a species or higher monophyletic taxon that is examined in the course of a phylogenetic study to determine which of 2 character states is derived and which is primitive

character

a feature or observable part of an organism, that may be described, figured, measured or weighed counted scored

Evolutionary Novelty

an inherited change of a previously existing character state to a new character

Homology

exist at several different levels

homologous feature

is something in 2 or more taxa that can be traced back to the common ancestor of these two taxa

Analogous character

is a similar character in two or more taxa that cannot be traced back to the common ancestor of those two taxa

Homologous

from two characters if one is directly derived from another

Convergence

similarity in a character or trait in distantly related taxa

Parallelism

independent acquisition of a character in closely related lines

Homoplasy

characters which display similarity but are thought to have arisen independently either from independent characters or from the same character at different times

Apomorphy

a derived character or evolutionary novelty

Plesiomorphy

a primitive character - in reference to a character found in an ancestor

Synapomorphy

a shared derived character

symplesiomorphy

a shared primitive character

analogy

analogous character is a similar character in two or more taxa that cannot be traced back to common ancestor

The five basic goals of taxonomist or a systematist:

1. Recognize, describe, and provide classifications of a new species

2. examine structure of populations

3. reconstruct genealogical history of lineages by estimating the hierarchy of relationships

4. examine the processes and components of speciation

5. examine biogeography