See also https://github.com/cmdcolin/oddgenes
This repo is similar to oddgenes in motivation, but I wanted to cover weird biology in general for things, even some genome related things, that didn't entirely fit into oddgenes.
So much of the entire tree of life is extremely odd in a way, so it is hard to draw any line for what qualifies for this repo, but I'll accept basically anything
Please free to make PRs for more stuff!
Here is a short summary of https://en.wikipedia.org/wiki/Non-random_segregation_of_chromosomes created by google gemini
- Aphids: During spermatogenesis, the X chromosome in aphids consistently moves to the larger daughter cell, which is the only one that produces sperm, ensuring all offspring are female.
- Butterflies (ZZ/Z0 type, e.g., Taleporia tubulosa): The Z chromosome's segregation in ZZ/Z0 type butterflies is influenced by temperature and maternal age, impacting the offspring's sex ratio.
- Butterflies (ZZ/ZW type): In certain ZZ/ZW type butterflies, the W chromosome always enters the egg cell, resulting exclusively in female offspring.
- Fungus Gnats: During meiosis II, the X chromosome in fungus gnats prematurely moves to one spindle pole, leading to sperm with two X chromosomes, although one is later eliminated.
- Flowering Plants (e.g., maize with the K10 chromosome): The K10 chromosome in flowering plants like maize preferentially enters the embryo sac, leading to its increased inheritance.
- Plants (e.g., Lilium callosum with B chromosomes): B chromosomes in plants such as Lilium callosum demonstrate non-random segregation, causing their accumulation in subsequent generations.
- Some Bug Species: In certain bug species, mechanically linked X chromosomes cosegregate.
- Giant Crab Spider (Delena cancerides): Free univalents, or unpaired chromosomes, show coordinated segregation in the giant crab spider.
- Various Neuroptera: Free univalents also exhibit coordinated segregation in various Neuroptera species.
- Alticini: Coordinated segregation of free univalents is observed in Alticini.
- Cricket (Eneoptera surinamensis): The cricket Eneoptera surinamensis also shows coordinated segregation of free univalents.
- Whirl Worm (Mesostoma ehrenbergii): Coordinated segregation of free univalents occurs in the whirl worm Mesostoma ehrenbergii.
- Northern Mole Cricket (Neocurtilla hexadactyla): In the northern mole cricket, sex chromosomes segregate before autosomes, with the univalent X1 chromosome moving to the opposite pole from the X2Y bivalent.
- Mangoes, cashews, and pistachio are related to posion ivy (https://www.scientificamerican.com/article/what-do-cashews-mangoes-and-poison-ivy-have-in-common/)
- Humans are more closely related to mushrooms than plants (https://gizmodo.com/why-are-mushrooms-more-like-humans-than-they-are-like-p-5940434)
- Humans are more closely related to a sea urchin than a fly or worm (https://www.abc.net.au/science/articles/2006/11/10/1785449.htm)
- Comb jellies are a sibling group to all other animals (not sponges) (https://www.mbari.org/news/genetic-research-offers-new-perspective-on-the-early-evolution-of-animals/)
- Oak trees are more related to pumpkins than to pine trees (https://www.youtube.com/watch?v=ONVpFtiD-fo)
- Horses are more closely related to rhinos than antelope (even vs odd toed ungulates, (https://positivepeerpressure.blog/quirky-evolution-5-unlikely-animal-relatives-hiding-in-plain-sight-6e08cfd299a7)
- Hyraxes (rodent-looking mammal) are more related to manatees and elephants than any other rodent (https://en.wikipedia.org/wiki/Hyrax)
- "There is no such thing as a tree" (or, woody trees are not 'monophyletic') (https://eukaryotewritesblog.com/2021/05/02/theres-no-such-thing-as-a-tree/) see also this TED video https://www.youtube.com/watch?v=j1EXBeBA89w
- "There is no such thing as a fish" (similar to above) (https://www.businessinsider.com/fish-do-not-exist-2016-8)
- Bats are more closely related to cows, whales, and pumas compared vs flying squirrels https://www.batcon.org/surprising-bat-relatives/
- Aardvarks are more related to manatees than they are to armadillos https://www.livescience.com/55241-aardvark-facts.html (bonus: Aardvarks are the only living species of their evolutionary branch)
- New world vultures and old world vultures are not very closely related, it is convergent evolution https://en.wikipedia.org/wiki/New_World_vulture
- Seals are more closely related to dogs than they are to cats, and even more closely related to bears https://www.youtube.com/watch?v=aAOsf004FqQ
- Shrews are more closely related to cats (and hedgehogs) than mice https://www.youtube.com/shorts/jRPiiXKmZIA
- Horses used to be smaller and have multiple toes, similar to a tapir, but it was reduced to where they walk on their "middle finger" https://www.sci.news/paleontology/modern-horse-toes-12022.html https://en.wikipedia.org/wiki/Evolution_of_the_horse
- Eukaryotes evolved from giant viruses? https://en.wikipedia.org/wiki/Viral_eukaryogenesis
https://en.wikipedia.org/wiki/List_of_examples_of_convergent_evolution
The concept of 'parental care' evolved independently in many lineages through convergent evolution
https://en.wikipedia.org/wiki/Parental_care
"Today I learned that the Atlas blue butterfly has 448–452 chromosomes. The highest number among non-polyploid eukaryotic organisms."
https://twitter.com/Jente_O/status/1653469755569782808
See also https://en.wikipedia.org/wiki/List_of_organisms_by_chromosome_count
"Our previous studies showed that male platypus has five X and five Y chromosomes, no SRY, and DMRT1 on an X chromosome"...additionally some of the X chromosomes have high homology to birds e.g. chicken
"Though the platypus lacks the mammalian sex-determining gene SRY, a study found that the mechanism of sex determination is the AMH gene on the oldest Y chromosome." https://en.wikipedia.org/wiki/Platypus#Evolution
https://genomebiology.biomedcentral.com/articles/10.1186/gb-2007-8-11-r243
More complete genome sequencing was done 2021 https://pmc.ncbi.nlm.nih.gov/articles/PMC8081666/
Like we have mitochondrial genome in our cells, this single celled organism has 7 different genomes in it's cell
https://phys.org/news/2023-04-single-celled-alga-harbor-genomes.html
Dental plaque bacteria elongates and then splits into 3-14 cells in a cell division https://www.sciencealert.com/bacteria-in-your-mouth-reproduce-in-a-strange-rare-way-scientists-discover
More info https://en.wikipedia.org/wiki/Fission_(biology)#Multiple_fission
Parthenogenesis is an embryo that grows directly from unfertilized eggs (https://en.wikipedia.org/wiki/Parthenogenesis)
Some species (e.g. whiptail lizards) are entirely female (https://www.scienceabc.com/nature/animals/are-there-any-all-female-species-in-the-wild.html)
There are other types of asexual reproduction as well https://en.wikipedia.org/wiki/Asexual_reproduction
https://biology.stackexchange.com/questions/77371/are-there-lifeforms-that-have-more-than-2-sexes
See also https://en.wikipedia.org/wiki/Sexual_system#List_of_sexual_systems
Seahorses are a common example where they will host the growing embryos
https://en.wikipedia.org/wiki/Male_pregnancy
There are a variety of 'reasons' why cannibalism and sexual cannibalism occurs, but it is common across the tree of life https://en.wikipedia.org/wiki/Sexual_cannibalism
There are other types of cannibalism also https://en.wikipedia.org/wiki/Cannibalism
See also: trophic eggs (eggs as food) https://en.wikipedia.org/wiki/Trophic_egg
A number of examples listed here https://en.wikipedia.org/wiki/Sexual_conflict
- Kangaroos have "three vaginas" https://grist.org/animals/kangaroo-genitals-are-weirder-than-you-ever-thought-possible-2/