Senescence
The biological process of aging—the gradual deterioration of functional characteristics over time. In cells, the loss of ability to divide and function properly.
Used in the Books
This term appears in 4 chapters:
"...ves burned (salmon don't eat during migration - live off stored fat from ocean feeding) - Mortality: 100% (all salmon die after spawning - programmed senescence, body shuts down) - Physical damage: Body deteriorates during migration (muscle wasting, immune system collapses, organs fail, fungal infections, ski..."
"In rainforest, height advantage is everything (shade = death). The environment sets the growth limit via competition intensity. Senescence: Programmed Growth Cessation Pacific salmon grow continuously for 3-5 years in the ocean. Then they swim upstream to spawn."
"...rks, allowing others to identify signal sources. Seasonal coordination: Mycorrhizal networks may help coordinate flowering timing, fruiting, and senescence across forest stands. Synchronized flowering improves pollination success (more pollen available when all individuals flower together); synchronized ..."
"But they pay the cost in short lifespans. High metabolic turnover damages cells, accumulating mutations and senescence. Large organisms process energy slowly - they grow slowly, mature late, and reproduce infrequently but benefit from low cellular turnover (less cumu..."
Biological Context
Senescence involves accumulated damage, telomere shortening, and declining repair mechanisms. Different species age at different rates, often inversely related to metabolic rate. Cellular senescence can be both protective (preventing cancer) and harmful (contributing to aging).