Silverfish VS Firebrats evolution inquiry

[silverfish]

Does anyone know of any major other differences between silverfish and firebrats? Other than the obvious of firebrats living in hot environments, I have read they seem to reproduce and lay eggs much faster than silverfish do- would anyone know why this could be?

Thanks

 

[wizentrop]

That is an incorrect pet hobby myth.
Every species is different, and the common names are usually meaningless. Some firebrat species are slow to breed, while some silverfish species are insanely fast and prolific, which is why they are regarded by many as pest species.

 

[silverfish]

That is an incorrect pet hobby myth.
Every species is different, and the common names are usually meaningless. Some firebrat species are slow to breed, while some silverfish species are insanely fast and prolific, which is why they are regarded by many as pest species.

I see. Thank you for the response. I suppose it was naïve of me to think they were all the same. Per my other question, would you happen to know if firebrats evolved to live in warmer climates? Did they branch off from the main insect silverfish themselves? Or were they always regarded as a separate species? I know they are both Zygentoma

 

[DaveM]

I see. Thank you for the response. I suppose it was naïve of me to think they were all the same. Per my other question, would you happen to know if firebrats evolved to live in warmer climates? Did they branch off from the main insect silverfish themselves? Or were they always regarded as a separate species? I know they are both Zygentoma

@wizentrop is the right kind of scientist to answer these questions (I'm not), so trust his answers if he is so kind as to respond to you.
In the meantime, however, I'm going to guess some things that he might tell you:

1) Firebrats mostly tend to live in warmer climates, which is practically equivalent to saying that they evolved to live in warmer climates. Insects like these end up getting distributed in small numbers all over the world due to stowing away in boxes and shipping containers, etc. etc.; there are no geographic barriers that they cannot cross (with our help). SO wherever they tend to establish themselves most will be in the most favorable ecological niches for their survival, i.e. that they evolved well to live there. That's not quite an absolute law for all living creatures. There could be forced migrations into unsuitable habitats, due to fire or floods or war or construction projects. Humans have technological adaptations that can allow us to survive in environments that did not shape the evolution of our particular species, e.g. under the ocean or in outer space, but most other species on our planet only have biological adaptations. There could be changes in the local ecology, like those due to climate change, rising sea levels swamping an inescapable island, introduction of invasive predators or competitors, desertification of forests, forestation of deserts, and many more. In general, when animal species cannot evolve to adapt to changes in their habitats, local populations die or on a global scale the species goes extinct. SO, by and large, wherever you see animal populations thriving: yes, they evolved to live there.

2) The evolutionary histories of firebrats and silverfish are not perfectly known, and not studied very extensively.
Here is a paper that can somewhat answer your question:

Characterization of the complete mitochondrial genome of Neoasterolepisma foreli (Insecta: Zygentoma: Lepismatidae) and the phylogeny of basal Ectognatha

Look at the inferred phylogeny (the tree figure toward the bottom of the paper). Within Zygentoma >> Lepismatidae, you can see that the silverfish (genera Lepisma and Ctenolepisma) shared an unnamed common ancestor with the firebrat (Thermobia). They both diverged from that common ancestor, which likely shared characteristics of both firebrats and silverfish. Chimpanzees are our closest relative, and though we might have a "higher" opinion of ourselves, it would be wrong to say that humans evolved from chimpanzees (or vice versa). Humans and Chimpanzees diverged from a common ancestor great ape, but both the human and chimpanzee lines have continued to evolve in parallel since then. We are present-day humans, and there are present-day chimpanzees, neither of our species being the same as that ancient common ancestor ape species, and neither of our modern species evolving from the other.

3) What gets regarded as a species depends on the opinions of scientists expert in the field. Nature comes with no labels. The labels are what people assign, and they can change over time as people learn more. The history of how these species have been classified and named is something you can look up. Is an eastern bluebird different enough from a western bluebird to justify being classified as a separate species, or are they different subspecies, or just regional behavioral and morphological variants? That's a matter of opinion, and the experts' opinions are what count for how we name them. But importantly, nature exists independently of how people choose to describe it, and the birds don't give two bird doodoos about what we think.