Inv. in the News

What is the latest news on Ancestral First Animals?

Recent genomic and chromosomal linkage analyses support sponges (Porifera), not comb jellies (Ctenophora), as the earliest-branching animals, suggesting that nervous systems and muscles evolved after sponges rather than being lost secondarily.

How do ants (and hymenopterans) determine sex of their offspring?

Through haplodiploidy: unfertilized eggs develop into haploid males and fertilized eggs develop into diploid females; recent studies show rare exceptions such as androgenesis and cross-species cloning in some ants.

What became of tube feet in the brittle stars?

Tube feet were secondarily lost in brittle stars; they are an echinoderm synapomorphy that was present in the ancestor but later reduced or eliminated.

Give one example of insects using electro-detection.

Bumblebees can detect floral electric fields, which change after other pollinators visit and help bees identify rewarding flowers.