Menoceras arikarense was a small rhinoceros that lived in North America about 22 million years ago. It had two horns on its nose positioned side by side.
Menoceras differs from other ancient rhinoceroses by the position of its two horns side by side on the nose. It is important for science because it shows how rhinoceros horns appeared and changed during evolution.
Legendary longevity: over 100 years. Galapagos tortoises, Greenland sharks, ocean quahogs celebrate with family once every 4 years
homogamy, reproduction always with fertilization, no alternation of generations
Offspring
Worker
Elders
leaves and stems of grasses and other herbaceous vegetation
Bro
birth time
normal sexual
woodland
Taxons
if born as {name}
wood, tree bark
Dogs, dolphins, lynx hang out for 9-25 years and party on their birthday three times a year
m
Map
will celebrate their {n} birthday
g
age
t
When your next jubilee falls in {name} life years
Human
birth date
no permanent shelter
rest
Close
was
days
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
Warm summer
The basics
How old you would be if you lived as {name}
Theoretical maximum lifespan estimated from the Dynamic Energy Budget (DEB) mathematical model. This value reflects a biological potential derived from metabolic parameters, not from direct observation — real recorded lifespans are often significantly shorter.
My weight?
74 to 150 kilograms, 1.4 – 3 meters
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
adult
Maturity
primary food sources
teeth
Potential Habitat
About health
When your next birthday would fall if you lived as {name}
d
In husbandry
On the go from 1.3 to 3.5 years. Forest mice, anoles, rainbow fish party on their birthday once a month
Motorcycle
Repro interval
results
Mass
young shoots and leaves of plants
Mosquitoes, fruit flies, small crustaceans hustle for up to 7 months and throw a birthday party every week
Plants
summer warm, winter not very cold
land
Colors
Sex
{name} birthday
Upcoming jubilees
Gremllins
mo
Teeth color
Nearctic realm
grass
No results found
North America and Greenland, from tundra to forests
Trophic type
Filters
branches
On the map
young shoots, sprouts, green plant shoots
all life stages
Female ♀
young shoots and sprouts
gnaws plants
leaves
Body color
grass
Upcoming birthdays
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
Potential habitat modelled from GBIF occurrence data. Map © Zveriki.com, licensed under CC BY 4.0.
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
Horns color
birth year
Maturity
Skin color
young are born live on land, not hatched from eggs or roe
grassland
sq mm
yr
Wanderers
protection from sun
How similar?
Jubilee = every 10th birthday
Male ♂
until the celebration
baby / chick
age as {name}
How do they breed?
On the go from 3.5 to 6 years. Hedgehogs, crows, lizards treat themselves to birthday snacks 6 times a year
What if eaten?
Neither
Earliest developmental stage inside an egg or womb.
Business sausages
Young offspring still dependent on parental care.
Mixed tree cover with moderate canopy and understory, supporting diverse woodland fauna.
Lifespan average
What do they eat?
leaves
Where do they live?
live birth
Hard dental structures used to bite, tear, or scrape food.
What do they look like?
Maturity
emergence (insects)
end of lifespan
How do they live?
fertilization / egg laying
How do they behave?
birth / hatching
metamorphosis / end of larval stage
end of acceleration
Share
Duration
Find a pet...
Mature, fully developed individual capable of reproduction.
Horns count
This is me
Gamers
Pets
How are they built?
Nearctic realm
shoots
mm
Theoretical lifespan
ml
Stars
Link copied
My age?
wk
My size?
Open terrain dominated by grasses with few trees.
{name} jubilee
Asexual
swap
cm
Old-timers
Find an animal or breed...
plains
turns
Rabbits, falcons, red-eared turtles hang out for 6-9 years and party on their birthday four times a year
Rascals
Where do they take shelter?
inhabit and develop on land, outside water bodies
Horns size
celebrated their {n} birthday
When you would have been born if you lived as {name}
Litter size
Daddies
Lifespan maximum
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
How to care for them?
Living from 25 to 40 years. Orangutans, bald eagles, African elephants celebrate their birthday twice a year
grazing
wood
°C
Not specified
Hermaphrodite ⚥
Where are they found?
North America and Greenland, from tundra to forests
Species lacks any fixed or lasting shelter structure.
embryo
herbivore
Length
kg
Feeds by cropping or nibbling low-growing vegetation or algae.
Observations
◉{N} more on tap