Wednesday, May 24, 2017

Sponges Reclaim Their "Rightful" Place on the Tree of Life

So in 7th grade I remember being taught that sponges were "the first group of animals to evolve" - or more aptly put now - the earliest branching animal lineage. This thus made the sponges the sister group to all other animals, and I went on believing this lie for many years. But then my whole life was uprooted when, in CCS bio, John enlightened us to the current interpretation of the tree of life where ctenophores (comb jellies) kicked sponges out of their original position on the tree of life. I was shook. But as I was looking further into this topic after class, I found a recently published paper which discussed a new phylogenetic analysis that took place and restored sponges to their original position on the tree of life. Yay!

The new analysis used a much larger and more robust data set for their phylogenetic analysis than any other previous study tackling the issue - using a set of 1,719 "high quality" genes and 79 species. The researchers found that the most parsimonious interpretation of their results yields a tree of life where sponges branch off first in the metazoans and are monophyletic. These results also remove the implication that neurons and muscle cells had to evolve twice in the animal lineage - once in the ctenophores, then being lost in sponges, and evolving once again in bilaterals - as would have been the case if ctenophores branched first.

Previous phylogenetic analysis studies likely developed a different view of the tree of life due to an artifact or error known as long branch attraction which occurs when organisms with a high rate of molecular evolution, such as ctenophores, are grouped together simply because of this high rate of molecular evolution. This groups lineages that are not necessarily related together and thus produces errors.

If you want to look into this study in greater depth, here is a link to the article:

Monday, May 8, 2017

What your parents aren't telling you about weed.

Weed. Marijuana. Mary Jane. Whatever you call it, it's a drug; it comes from a plant; and it can make you high. It's also used as a pain killer. You probably already knew all of this. But what I bet you didn't know is that new research suggests that marijuana may be able to reverse aging!! This is probably because WHO WOULD HAVE THOUGHT and also
because the paper was just published today. Believe it or not, researchers were able to return the state of old mice to that of two-month-old mice with prolonged low-doses of THC. They are now looking to start clinical trials in people. This novel role for marijuana holds exciting possibilities for the development of future treatments for age-related diseases such as dementia. Read the full article at the link below. Crazy stuff man!

Tuesday, May 2, 2017

Fancy New Species

Hey guys!
So after Claudia talked about the cool new species in class I did some research to see what else was discovered recently.
My personal favorites are

Lasiognathus Dinema - this is a type of Angler fish living at depths below 500m. The thing that drew me to this was how crazy it looked! I feel like most biologists have an idea of what an angler fish is supposed to look like (especially with movies like Finding Nemo) but check this out!

Lasiognathus dinema, female about 30 mm long. Image credit: Theodore Pietsch.

It was discovered very recently so there aren't really any papers on it, but here's an article talking about its discovery.

Phyllopteryx Dewysea - also known as the Ruby Seadragon. Not only does this look pretty cool since it is related to seahorses, but it is only known from 4 preserved specimens!

Image result for Phyllopteryx dewysea

Recently it was found in the ocean and they actually got a video of it! Check out the video here.

Anyways, I thought these were pretty cool. Unfortunately there isn't too much research on either of these due to a lack of availability (only 4 ruby seadragons found, and the angler fish is super deep and very rare/hard to find) but hey if you're interested it seems like a cool area of research!