Using the Taxonomy database ANSWERS

Answers to the Using the Taxonomy database exercise

Answers by: Rasmus Wernersson and Henrik Nielsen. Last update: Aug 2026

Question 1:

• 1a: "Metazoa" Taxonomy ID: 33208
• 1b: Familiy containing humans: Hominidae
• 1c: Yes, humans are certainly vertebrate (we have a spine), and that can been seen in the taxonomy by looking at the "full lineage" and seing we're members of the group "Vertebrata".

Question 2:

Lowest ranking taxonomical group shared by Human (TaxID: 9606) and Mouse (TaxId:10090)

• 2a: (abbreviated lineage): Mammalia (rank: class) - Eng: Mammals
• 2b: (full lineage): Euarchontoglires (rank: superorder) is the last common group before human and mouse branch off into primates and rodents. This is a group of placental mammals.

Question 3:

Lowest ranking taxonomical group shared by Human (TaxID: 9606) and Fruit Fly (D. melanogaster - TaxId:7227)

• 3a: (Abbreviated lineage): Metazoa (rank: kingdom) — this is the group of all animals.
• 3b: (Full lineage): Bilateria (rank: clade (which just means a group) — sits between kingdom (Metazoa) and phylum (Chordata for human, Arthropoda for the fly)).

Question 4:

a)

The sister group to the Zebrafish is the cod.

The sister group to the lungfish is the Coelacanth (famous "Blue fish").

b)

Now, the sister group to the lungfish is you!

c)

you

d)

you

e)

you

f)

No! See https://www.sciencealert.com/actually-there-is-no-such-thing-as-a-fish-say-cladists

Question 5:

a)

Yes, there is a difference.

b)

Yes, the trees can be made identical by swapping the Coelacanth and the lungfish.

Question 6: (AI assisted analysis)

No single answer can be given here - we'll discuss some example in class next week as part of the wrap-up.

In august 2026 a simple query Google AI with the question "Does the category "fish" make any scientific sense? " gives a rather good overview explanation (see screenshot below).

NOTICE: It's clear that the AI has sourced (some of) the information from the Science Alert article we have also given as a reference under the answer to Q4f above.

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We can ask the AI to dig deeper and add more scientific rigor by adding the prompt:

Follow up by expanding the answer with more scientific rigor. 
Cite real scientific sources. This can both be scientific publications as well as 
scientific reference databases (for example, but not limited to, NCBI Taxonomy).

This gives an answer broken down into the parts below. It is certainly possible to write it in a more concise manner, but it does capture the main points, and includes references beyond popular science articles and wikipedia. Notice that part 2 specifically talks about the distance in relationship between several of the brances of the tree we also have in our analysis (we use Cod, the analysis here uses Salmon as an example - both cases includes human and the lungfish).