1.2 Chapter 1-6 Animal Evolution: Key Concepts (Fill-in-the-Blank Flashcards)

A set of 30 fill-in-the-blank flashcards capturing key concepts from the lecture notes on animal evolution, phylogeny, basal groups, chordates, and major evolutionary events.

The group __ includes mammals, birds, reptiles, amphibians, and fish.

Craniota

A phylogenetic tree is used to display patterns of __ ancestry.

common

A clade includes an ancestral species and all of its __.

descendants

A monophyletic group contains a single __ and all of its descendants.

ancestor

A paraphyletic group includes an ancestral species and __ of its descendants.

some

Porifera, or sponges, lack true __.

tissues

Choanoflagellates are the closest relatives of __.

animals

Craniota refers to animals with a __ (skull).

cranium

Invertebrates are not a __ group.

monophyletic

The basal groups discussed include Porifera, Ctenophora, Placozoa, and __.

Cnidaria

Ctenophora are comb jellies that move by beating __.

cilia

Placozoa are tiny, simple animals with two tissue layers and no __.

organs

Cnidarians possess stinging cells called __.

nematocysts

Tenophora lack __.

synapses

MicroRNAs evolved after tenophora split off, and they were lost by __.

Placozoa

The four major chordate synapomorphies include a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a __ tail.

post-anal

The dorsal hollow nerve cord develops from __ cells.

ectoderm

Hagfish and lampreys are examples of __ (jawless vertebrates).

agnathans

Jaws first evolved in the group __.

Gnathostomes

The amnion is a membrane that allows development on __.

land

Most amniotes have eggs surrounded by a __.

shell

Within Craniata, hagfish and lampreys are examples of __.

agnathans

Nerve cells in tenophora and other groups may reflect a __ (convergent evolution) in nerve cell evolution.

homoplasy

Birds diversified enormously 55–65 million years ago, likely after most dinosaurs went __.

extinct

Schultz et al. found that tenophora chromosome patterns resemble those of __ relatives.

single-celled eukaryotes

A node from which more than two __ emerge, indicating unresolved relationships.

lineages

Protostomes are divided into Spiralia and __.

Ecdysozoa

Ecdysozoa includes nematodes, tardigrades, and all __.

arthropods

Cnidarians host symbionts called __ that provide nutrients via photosynthesis.

zooxanthellae

Bird diversification after the dinosaur extinction created many new __ for birds.

niches