Classification Flashcards

1
Q

Main principle in classification?

A

Groups must be monophyletic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why are vernacular names preferred?

A

Based on the language of everyday life, so don’t need to memorise or pronounce the Latinised scientific name.

Can refer to the appearance of the organism, making it easier to remember.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Problems with vernacular names?

A

Common names often have a very local distribution, so one organism in an area may have several names.

Common names can change with time.

A single common name may refer to more than one species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Advantages with scientific names?

A

Names are associated with groups, so allows for relationships to be drawn between species.

Clarity - each species will only have one scientific name.

Universal - scientific names are standardised and accepted universally.

Interspecific relationship - help understand the similarities and differences between species of the same genera.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define taxonomy?

A

Science of naming, describing and grouping living organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define phylogenetics?

A

Study of evolutionary relationships between/within groups of organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define systematics?

A

Inference of phylogenetic relationships between species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define dichotomous?

A

Divides into 2 branches.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define monophyletic?

A

All share a common ancestor and contains all the descendants from a certain ancestor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What were early attempts at classification based on?

A

Intuition (Theophrastus 371BC) or morphology (Dioscorides 1st century)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What did Gesner do?

A

Used more than one characteristic to classify. 16th century.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What did John Locke do?

A

Talked about how it was possible to guess the primary essence by observing as much of the secondary essence as possible. 17th century.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What were John Ray’s contributions?

A

Species definition: a group of individuals who share a unique combination of characteristics that can be replicated.

To preserve a species you need to grow plants from seeds to maintain sexual reproduction.

To classify you need to use as many characteristics as possible and allow for losses.

Don’t allow for one characteristic to become the priority.

His defined monocots have been shown to be monophyletic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Linnaeus’ contributions?

A

18th century.

“Without permanent names there can be no permanence of knowledge”

Used binomial names for each species.

However, chose reproduction as the priority which was a step backwards.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Bentham and Hooker’s contributions?

A

19th century. Rejected Linnaeus and brought back Ray.

Used a hierarchical system. Defined the KPCOFGS system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Darwin’s contribution to classification?

A

Explained the apparent hierarchical pattern.

“Hidden bond of community of descent”

17
Q

Watson and Crick’s contribution to classification?

A

Discovered DNA structure in 1953. By 1970 it was possible to DNA sequence.

Darwin’s “hidden bond of community of descent” was revealed.

18
Q

How can a phylogeny be made more robust?

A

Using more characteristics and DNA sequencing.

19
Q

What else can be used for sequencing other than DNA?

A

Proteins, as these drive the cell’s behaviour and also evolve.

20
Q

Summary of the APG 1 Paper?

A

Angiosperm Phylogeny Group 1. 1998.

Added more accurate resolution to the phylogenetic tree at a family level.

Some of the proposals were completely unexpected when compared to a solely morphological tree, showing that morphology alone isn’t enough.

The molecular data did confirm that most of the families based on morphology were monophyletic - 73%.

Of the remaining 27%, 13% were amended in this classification, the other 14% were left unclassified.

Angiosperms were the first large group to be reclassified based on genetics.

No longer dicots and monocots as dicots weren’t monophyletic.

21
Q

What is the APG?

A

Angiosperm Phylogeny Group.

A classification system was published in 1998, 2003, 2009 and 2016.

Motivation were the deficiencies in the phylogeny due to non monophyletic groups.

22
Q

Why should be try to name and group all of the world’s organisms?

A

Identification and organising information - need a stable universal system in order to identify organisms.

Conservation - identify biodiversity hotspots to allocate resources to. Establish links between phylogenetic diversity and conservation strategies.

Crop breeding - identifying genes in wild relatives could be a quicker, more specific way of breeding new varieties.

Revealing evolutionary history

Support for theory of evolution

Understanding biogeography - can reveal patterns of distribution, migration and adaptation.

Predicting traits - can predict characters without needing to investigate each species

Searching for medicines - related species often produce similar chemicals and thus if a pharmaceutical molecule is found in one species, its relatives are worth investigating

23
Q

Example of how a phylogeny has changed?

A

The arthropod tree now links insects with crustaceans as a group of Pancrustacea, not with centipedes and milipedes (Myriapods) as was once thought.

24
Q

Example of a ring species?

A

Euphorbia in the Caribbean looks like a candidate for the first plant example.

25
Q

What is a ring species?

A

Connected series of neighbouring populations, each of which can interbreed with closely sited related populations, but for which there exist at least two “end” populations in the series, which are too distantly related to interbreed

26
Q

Example of a useful predictive trait?

A

Members of the potato family are often toxic and can be useful to pharmacology.

27
Q

Example of how searching for medicines is made easier with phylogenies?

A

Galantamine was originally extracted from snowdrops, but the closely related daffodils can produce more and make a better crop.

Used to show the development of Alzheimer’s disease.